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Sibling Relationships

Sibling Relationships

Relationships with extended kin, spouses, parent and child, and siblings are all affected by a changing social world. Family size (one indicator of sibling structure) is shrinking in many societies. The International Database of the U.S. Bureau of the Census (2001) reports an all-time low of 2.76 children per woman, down from 4.17 in 1960. Growing up with fewer siblings (or none, as is mandated in much of China) has profound implications in terms of intrafamily relationships, inheritance possibilities, and obligations and responsibilities for family members.

Dimensions of the sibling relationship. Sibling relationships can be analyzed according to a number of factors, including position within the sibling system, roles assumed by different siblings, family norms for children's expected behavior, the extent of coalition formation within the sibling system, and the functions siblings perform for each other. Expected behavior for siblings may depend on where the child is in the sibling hierarchy (oldest, middle, or youngest child) and whether the child is male or female. At all ages, sisters are reported to be, and report themselves to be, closer to one another than are brothers or cross-sex sibling pairs. Position and sex may dictate role behavior (e.g., who assumes outside versus inside chores or acts as caretaker for younger siblings). Coalitions foster sibling solidarity, counter the power of parents or other sibling subgroups, and develop to strengthen siblings' positions in times of conflict. Siblings serve many functions for one another. Some of these include serving as a "testing ground" for one another when experimenting with new behaviors or ideas before exposing them to parents or peers; serving as teachers; practicing negotiation skills; and learning the consequences of cooperation and conflict and the benefits of commitment and loyalty. Older siblings may serve a protective function, "translate" parental and peer meanings for younger brothers and sisters, and act as pathbreakers when new ideas or behaviors are introduced into the family. For example, parents may object less when a younger son decides to get his ear pierced, or a younger sister decides to have the small of her back tattooed, because an older sibling already weakened parental resistance. Lastly, it is within the sibling group that children first experience feelings of fairness and justice. Siblings compete for resources within the family, and if resources (such as affection, time, attention from parents, space, or material goods) are scarce, children watch closely to ensure that they are getting their fair share (Ihinger 1975). What appears to distinguish middle childhood sibling behavior of children in the United States from its non-Western counterpart is that it reflects a family system based upon independent relationships. It mirrors the prototypical Western family as a culture of individualism (as compared to a culture of collectivism). The consequence of such behavior is intergenerational and interpersonal independence (Kagitcibasi 1996).

Sibling Similarities and Differences

Despite commonalties of shared factors such as social class; physical and mental health of family members; the parental relationship; the emotional climate of the family; and the child-rearing skills, values, and attitudes of parents, siblings are a good deal different from one another. Only about 50 percent of siblings' genetic background is shared. In terms of weight and height, they are about 50 percent similar, and the correlation between siblings and their IQ scores is only .47 as children and .31 as adults (Dunn and Plomin 1990). By comparing the shared and nonshared family experiences of siblings, it can be seen that differential treatment and expressions of affection and interest by parents and other kin, perceptions of this differential treatment by siblings, and the effects of peer groups and school experiences coalesce to create a separate "life" for each child growing up in the same family.

Siblings in Non-Western Cultures

Siblings have important and unique roles and functions to perform within the family. These vary, however, according to the cultural context. In Western societies, the sibling relationship tends to be identified by biological or genealogical criteria and it is typically less important than the spousal or parent-child relationship. In contrast, in some non-Western societies, a sibling may be more important than a spouse; in others, cousins may be considered siblings (Adams 1999). Victor Cicirelli (1994) cautions that it is important to be aware of how sibling is defined in the particular culture that is being discussed. For example, in the Malo culture of New Hebrides in Oceania, all cousins of the same sex, the parent's siblings of the same sex, and grandparents of the same sex are considered to be siblings. In the Marquesas culture of Oceania, however, only full biological siblings are identified as siblings.

Many important family functions, such as taking care of younger children and teaching them basic household and occupational skills, are carried out by siblings in non-Western societies. Childcare is usually a shared activity that takes place in the context of other activities such as doing chores, participating in games or play, or just lounging. Sibling caretaking serves several major functions for a family and community. It supports parents who must spend their time in vital subsistence tasks, serves as a training ground for parenting, provides exposure to important superordinant and subordinate role behavior that will have to be carried out later in adulthood (e.g., male and female roles), and stresses interdependence—an important characteristic of the group in which the children will live (Weisner 1982). Thus, interdependence and mutual support between siblings is highly valued and is learned at very early ages (Nuckolls 1993). A family system that is characterized by a culture of collectivism develops from such interdependence. So strong is this interdependence that in much of the world siblings are a major influence in the life course of their brothers and sisters. As adults, they may help arrange marriages and provide marriage payments for each other. "They share life crisis and rite of passage ceremonies essential to their cultural and social identity; they take on ritual and ceremonial responsibilities for each other essential to community spiritual ideas" (Weisner 1982, p. 305). This culture of collectivism persists even in the face of social change. A study of adolescents found that youth in Asia and Latin America (collectivistic cultures) held stronger family values and higher expectations regarding their obligations to assist, respect, and support their families than did their European counterparts (Fulgini, Tseng, and Lam 2000).

Interdependence does not, however, eliminate conflict and disharmony. In non-Western societies, whether descent is traced through the mother or father's lineage, two distinct dimensions of adult sibling relationships have been identified. One of these is competition for inheritance and property-holding; the other is joint obligation to parents. Within a patrilineal society there are a variety of ways property can be transmitted. Family property may be inherited by the first-born son or the last-born son, or given to all sons partially. Yet another way of property distribution involves giving sons undivided shares so that siblings have to stay and work together for their collective interests and property. In matrilineal societies, family property passes through the female line but males still have rights of inheritance. Tension over the division of family property often occurs between a man and his wife's brothers (Adams 1999).

In Taiwan there is a unique family structure called take-turn stem families where siblings make an arrangement, according to a timeline, in which parents will live with them. Siblings take turns and cooperate to support and take care of their parents. Caring for parents often brings siblings into close and frequent contact with each other.

Age and sex are major determinants of sibling status in most parts of the world. An ancient Confucian code for family socialization in Chinese society was as follows: "Fathers should be kind to their children, and sons should be obedient to their parents, and older brothers should love their younger siblings, and younger brothers should respect their older ones." Following this code, children (especially the first son or daughter) were socialized to provide material and emotional support for one another at an early age. Older brothers replaced parental roles and inherited parental authority in the absence of a father whereas older sisters served as a backup system of caregiving for younger siblings. However, sisters had no control or power over them, especially younger brothers. Younger brothers and sisters were expected to obey and respect their older siblings, particularly the big brother, as if he were in the parental position (Tsai 1998). Modernization and economic development have modified these norms. When the one-child policy was first introduced in China in 1979, its aim was to prevent rapid population growth. In urban areas, particularly, this policy succeeded, with a dramatic decline in the Chinese birth rate. The fertility rate was 5.8 per woman in 1960; 5.3 in 1970; 2.5 in 1980; and 1.82 in 2000 (Census Bureau 2001; World Bank 1984, 1993). However, changing a society's norms about how many children to have when male children are more highly valued than female children is problematic when the odds are high that the one and only child conceived will turn out to be a girl. Increasing rates of infanticide, the crippling of first-born girls in order to get permission to have a second child, among other considerations, brought about a slight relaxation of this policy for parents with special needs: if, for example a child was disabled or the first-born was a girl (Shen 1996). There are profound consequences for a society's families when a large majority of couples have only one child. Over time family structure and relationships are transformed when there are no kin to call brother, sister, uncle, aunt, or cousin.

In the following section the focus is on one Western society, the United States. However, although the details vary, similar interpersonal processes of conflict, competition, cooperation, learning, and teaching take place within the sibling group, just as in non-Western societies.

Sibling Relationships across the Life Span

In the United States, sibling relationships are dynamic and vary depending on the stage in the life cycle; they are no less important during old age than when children are toddlers or adolescents. However, what one expects from and what one gives to a sibling in old age is different from expectations and exchanges at earlier ages.

Research on infant and preschool siblings. There is growing recognition that siblings play potentially important roles in socializing each other's social, emotional, and cognitive development. One example of the effects of this socialization role is the finding that older siblings are not as accommodating to young children as adults are and thus encourage the development of pragmatic skills in their younger siblings. In other words, older siblings will make younger children perform such tasks as tying their own shoes and getting their own bowl of ice cream.

Psychologists studying the interaction patterns of preschool children and their infant siblings report that the arrival of a newborn in the family has immediate consequences for older siblings' adjustment and behavior. Bed-wetting, withdrawal, aggressiveness, dependency, and anxiety are among the most problematic behaviors reported in these studies (Dunn 1995). Positive roles for older siblings include the opportunity to learn caretaking skills and serving as models for appropriate social and cultural behaviors. Numerous studies find that young siblings benefit from observing and imitating their older brothers and sisters. This happens because older siblings "engage in activities during interaction that are within the scope of actions that the younger child is capable of reproducing immediately or slightly after observation" (Zukow 1989, p. 85).

Sometime between their third and fourth year, older siblings begin to take a more active interest in younger siblings, and brothers and sisters become both more effective companions and antagonists at this age. Older siblings demonstrate a clear understanding of how to provoke and annoy a younger child as early as age two. Countering this negative tendency is an increasing interest in alleviating the distress of others during the second year. There is some evidence that the way mothers talk to an older sibling about a newborn child is associated with the quality of the behavior between the children over time (Dunn 1995). Children become increasingly more involved with their older siblings during the preschool years.

Sibling relationships in middle childhood. American children become more egalitarian during the middle childhood years. When fifth- and sixth-grade children were asked about the relationship with their siblings, the quality noted most was companionship. This was followed by antagonism, admiration of sibling, and quarreling (Furman et al. 1989). These positive and negative qualities of the relationship were independent of one another, illustrating the ambivalence and complexity of sibling interaction. Younger siblings report feeling more affection, closeness, and respect for older siblings than the reverse.

Brothers and sisters tend to influence each other's gender role development. Boys with sisters score higher on expressiveness than boys with brothers, and girls with brothers score higher on competitiveness and assertiveness (Sulloway 1996). Boys with only brothers are reported as being more violent than boys with sisters (Straus, Gelles, and Steinmetz 1980).

A study of the relation between parental behaviors and sibling behaviors found that negative parental care (hostile/detached behavior) was associated with sibling quarreling/antagonism among children in middle childhood. Differential treatment by mothers is associated with more conflicted and hostile sibling relationships (Boer, Goedhart, and Treffers 1992).

Adult sibling relationships. A large majority (about 80%) of adult Americans have at least one living brother or sister (Connidis and Campbell 1995). Because of their shared past, and because they are typically close in age, siblings are potential sources of financial, physical, emotional, and psychological support and assistance in old age. Some of the topics related to adult siblings that have been investigated include the frequency of contact, feelings of solidarity and closeness, use of siblings as confidants, and types of support and assistance exchanged.

Those who study adult sibling relationships report four consistent findings. First, sibling contact and closeness is greater between sisters than in brother-brother or brother-sister combinations. Overall, women are more likely to be the ones to initiate and maintain kin ties, including those with siblings. Second, geographic proximity is a key factor in predicting the extent of adult sibling interaction. When siblings live close to one another they maintain contact, exchange goods and services, and support one another to a greater degree than when they live apart. Third, there is a curvilinear relationship between age and feelings of closeness, contact, and meaningfulness of the sibling tie. Relations are close during early and middle childhood, they decrease slightly during adolescence and middle age, and increase as individuals near the end of the life cycle. Almost two-thirds of adults report that they are close to their grown-up siblings and 78 percent feel they get along well with them (Cicirelli 1991). Fourth, sibling ties appear to be more salient for the unmarried and childless than for those who are currently married and those with children (Campbell, Connidis, and Davies 1999; White 2001).

In the process of studying sibling relationships, when methodological analyses are complex and include or control for the large variety of factors that influence adult sibling interaction (marital status, presence and number of children, number of siblings, income and educational status, age, presence of living parents, and race/ethnicity), the complexity of sibling interaction becomes evident. For example, one longitudinal study reported that giving and receiving help and assistance increasingly declined between the ages of twenty and seventy, then took an upturn—for siblings living close to one another. No upturn was evident for those who lived twenty-six miles away or further. When siblings lived close by, help was given more often by those with higher education; when there were more siblings in the family, help was more often given by sisters; and help was less likely to be given when parents were still alive (White 2001).

One similarity between the adult siblings in the United States and Taiwanese siblings discussed earlier is a reported closeness between siblings who provide care for elderly parents. When there is an emotionally close sibling network, the likelihood is much higher that all siblings will share in the support and care (Matthews 1987).

Some life experiences affect sibling closeness, improve relations, or increase the frequency of contact among adult siblings. Ingrid Connidis (1992) found that sibling ties were heightened when divorce, widowhood, or health problems occurred. However, when siblings married or had children, the relationship did not change. Lynn White (2001), on the other hand, found that getting married and having children decreased sibling contact and exchange among siblings.

Gary Lee and Marilyn Ihinger-Tallman (1980) examined whether sibling relations increased the morale of elderly persons. They found that siblings acted as companions, provided emotional support, shared reminiscences, and validated each other's sense of self, but they did not influence each others' degree of life satisfaction, disappointment, or pleasure in life. This finding underlies the more common "benign" exchanges that occur among elderly siblings. Although they may hold high regard for one another, sociability usually consists of telephone calls and visits to one anothers' homes: just sitting around talking and discussing matters of mutual interest—ordinary as opposed to exciting conversations (Scott and Roberto 1981; Allan 1977). Reminiscences are particularly valued because siblings were witnesses to the changes that took place during an individual's life (Connidis 1992). In a now-classic study, Bert Adams (1968) suggested that such mundane contacts are sufficient to meet the general obligation adult siblings have to maintain the relationship.

Stepsiblings and Half-Siblings

Half-siblings. The number of households that include either a half- or stepsibling increased 21.4 percent between 1980 and 1990 (Statistical Abstract of the United States 1994). Demographers predict that 33 percent of all children will live with a stepparent before the age of eighteen, and the predominant type of family form will be a stepfamily by the year 2010 (Visher, Visher, and Pasley 1997).

Stepsiblings. When children from different family backgrounds are brought together to live in the same household, the new situation contains more ambiguities and fewer guidelines than exist for full brothers and sisters who live in first-marriage families. For example, they generally have had few opportunities to get to know and adjust to one another before living together; remarried family boundaries are more fluid and children may come and go, visiting a parent, perhaps moving in for a period of time; stepsiblings have no shared family "history" that helps to develop common habits, values, customs, and expectations; and changes in family size, place in the family, status, and role expectations may precipitate strong emotional reactions in children. However, children tend to be adaptable and, in general, stepsibling relationships are characterized by positive affect even though they are not as close as those of full siblings (Ganong and Coleman 1995). Marilyn Ihinger-Tallman (1987) proposed seven conditions under which stepsiblings develop positive feelings for one another: frequent contact; shared experiences; family conditions fostering intimacy and interdependency; similarities in age, sex, values, and family culture; mutual benefit from association; perceived equality or equity of the children's changed circumstances and new living arrangements; and a minimum of competition over scarce resources (e.g., parental time).

According to Lawrence Ganong and Marilyn Coleman (1994) half-siblings who live together commonly call themselves brother and sister, rarely using the term half. Only when children have little to do with each other (i.e., they do not share vacations or other time together) do they tend to use the term half-sibling. Anne Bernstein (1997) proposed several factors that help develop strong relationships between half-siblings. These include a parental remarriage that is well established; a larger age gap between half-siblings; a shared residence; fewer children belonging to each spouses; sharing a mother as opposed to sharing a father; same sex; and similar temperaments.


The focus on cross-cultural sibling relationships centered primarily on the Far East, where scholars have concentrated attention on structural and cultural factors (i.e., birth-order, gender effects, inheritance, and socialized interdependencies). From an observation of the shifts in family size and structure, one might conclude that the values of individualism and utilitarianism that characterize family relationships in Western societies will erode the traditional values that are at the basis of non-Western societies (e.g., a preference for many children and for sons, an emphasis on interdependence and community). Testing this supposition, Cigdem Kagitcibasi (1996) examined several cross-cultural studies and concluded that in spite of global changes in social structure and economic changes, the collectivistic cultures that emphasize interdependence among family members continues, at least in the Far East (i.e., Japan, China, Taiwan, and Hong Kong). He did observe in both Western and non-Western societies that a change in family relationships is occurring in the patterns of interdependence: material or instrumental support is decreasing whereas emotional interdependence in increasing. Other scholars find that the traditional values of the importance of children and family obligations remain intact in the Far East in various degrees (Cho and Shin 1996; Shen 1996). Whether the patterns of interdependence and obligation among siblings will change or remain stable remains to be seen.

Focus on one Western nation, the United States, found that social science investigators have tended to examine sibling relationships at the interactional level, focusing on different stages of the life cycle. Growing up with their siblings, stepsiblings, and half-siblings, children act (either positively or negatively) as socializing agents, caretakers, playmates, teachers and role models. Across the life span, the majority of individuals report feeling close to their siblings, yet only a minority depend on these kin for intimate companionship or for financial, emotional, or physical assistance when they are adults. However, certain life experiences (e.g., never marrying, having no children, becoming widowed, or experiencing divorce) can produce closer contact and greater feelings of closeness among siblings. For the majority of people, interactions with siblings are positive and lead to the development of an affectionate life-long bond.

One could characterize sibling relationships in the United States as reflecting a culture of individualism that creates both intragenerational and interpersonal independence. This individualism and independence has, in most cases, resulted in affection, concern, and interest in brothers and sisters but with no accompanying obligation or responsibility for frequent contact or mutual aid (Rossi and Rossi 1990).

See also:Academic Achievement; Aunt; Birth Order; Childcare; Communication: Family Relationships; Conflict: Family Relationships; Cousins; Development: Cognitive; Development: Emotional; Development: Self; Family Business; Family Roles; Favoritism/Differential Treatment; Gifted and Talented Children; Kinship; Only Children; Primogeniture; Self-Esteem; Stepfamilies; Uncle


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Sibling Relationships


Siblings are family members who are ascribed by birth (full siblings), by law (adopted siblings) or by marriage (half-siblings, step-siblings, and siblings-in-law). Full siblings have two biological parents in common, whereas half-siblings have one biological parent in common. Legal siblings and step-siblings have no biological parents in common, but their parents are married. A sibling-in-law is related to ones spouse rather than ones parent, in any of the previous ways mentioned. A sibling-in-law can also be the spouse of ones siblings. Social siblings are friends or non-sibling relatives who are transformed into siblings informally, or, in some cultures, through a formal ceremony.

Research on siblings in old age has been limited primarily to full siblings. Important exceptions are the General Social Survey (GSS), which uses nationally representative samples, and the National Survey of Families and Households (NSFH), based on data collected in 1987 and 1988. Both studies include data on step-siblings. Only the NSFH includes data on siblings-in-law (siblings of ones spouse and spouses of ones siblings). Neither study has data on social siblings.

Many questions arise when considering siblings among older adults, including: (1) Do older adults usually have living siblings? (2) How many living siblings do they typically have? (3) Can future older adults expect to have living siblings? (4) How important are siblings to older adults? (5) What do siblings do for one another in later years? (6) What factors influence what siblings do for each other and how they feel about each other?

Prevalence of siblings in later life

Most older adults have at least one living sibling. According to the General Social Surveys data from the mid-1980s, the majority of community-dwelling older adults are likely to have a sister until age eighty-five and a brother until age eighty. This sex difference is likely due to the gender mortality gap, whereby men predecease women by seven to nine years, on average. In general, however, a high proportion of older adults has at least one sibling until the mid-eighties, when a precipitous drop occurs. This pattern is shown in Table 1.

According to General Social Survey data, the number of living siblings an elderly person has depends on the age of the older adult and the sex of his or her siblings. The majority of respondents who had any sisters had two or more until their early eighties while the majority of respondents who had brothers had multiple brothers until their mid-seventies. Whether future older adults can expect to have at least one sibling until advanced old age depends upon two factors. One is the fertility pattern for the birth cohorts in question; that is, the number of babies born to the parents of the older adults. In large families, one would expect a larger pool of potential siblings to survive into old age. The second factor is life expectancy for the cohorts in questiona longer life expectancy is related to the survival of a greater number of siblings. Assuming the dramatic increases in life expectancy of the twentieth century will be sustained, if not increased, in the twenty-first century, then fertility rates will be the determining factor.

Fertility rates declined in Western societies during the nineteenth and twentieth centuries; meaning that families have been producing fewer numbers of offspring. Amidst this general decline, however, a baby boom occurred immediately following World War II (between 1946 and 1964, approximately), thereby increasing the potential pool of siblings who might survive into the baby boomers old age. The fertility of baby boomers children on the other hand, appears to be substantially lower than that of their parents, thereby returning to the overall general decline in family size. Predictions tend to support a drastic reduction in siblings after the baby boom. However, these predictions do not seem to take into account the higher life expectancy and the increase in blended and reconstituted families.

Table 2 shows cohort trends in the number of siblings (dead or alive) for people born between 1911 and 1980. One-child families (respondents with no siblings) were most common during the Great Depression and the decade preceding it; but, for all cohorts, one-child families were the exception rather than the rule. Comparing current older adults with baby boomers, greater proportions of boomers have ever had two, three, four or more siblings than war babies. The post-boomer cohorts show a reduction in the number of siblings, so that a larger proportion have one and two siblings, but 30 percent of post-boomers still have four or more siblings. Because these siblings are more likely to survive into old age than those of earlier cohorts, predictions of greatly decreased availability of siblings in later years may be exaggerated, especially when all varieties of siblings are considered.

How important are siblings for older adults?

As seen above, until very old age, adults are likely to have at least one sister and/or brother. There is little doubt that siblings are highly valued in later life. This value is based on: (1) physical proximity and the amount of contact siblings have with one another, (2) the functions they serve one another related to contact, and (3) the functions they serve one another independent of contact. As will be seen, the third, symbolic function tends to best capture the importance of siblings for older people.

Sibling proximity and contact. Based on a representative sample of black and non-Hispanic white Americans age fifty-five and older (Minor and Uhlenberg, 1997), about 30 percent live between two and twenty-five miles from their nearest sibling. Just over 20 percent live at least 300 miles apart. As for the remaining 50 percent, most blacks (41 percent) have a sibling neighbor (within two miles) while whites are nearly evenly split between having a sibling neighbor (22 percent) and having a sibling between 26 and 299 miles away (25 percent).

Sibling contact (visits, phone calls, and letters) decreases in the course of adulthood, but in later life it increases somewhat. Adults generally maintain contact with their step- and half-siblings, but less than they do with full siblings. Whether this pattern is found for older adults as well is not known at this time. In general, sibling contact is meager. In an Indiana study (see Cicirelli, 1995), only 17 percent of the older respondents saw their most frequently contacted sibling weekly or more often, and one third saw their sibling monthly. The most typical frequency was several times per year.

What do siblings do for each other? Most studies confirm that siblings do not provide much instrumental support (e.g., performing household and other tasks) for each other in later years. Of those with a sibling within twenty-five miles, providing and receiving help with transportation is the most common form of instrumental support, yet such support is found only for 6 percent (providing transportation) and 5 percent (receiving transportation help) of older adults. Expressive support (e.g., advice, encouragement, moral or emotional support) can be transmitted and received from any distance and is more common, with 14 percent receiving and 16 percent providing expressive support. Some of these percentages vary by ethnic communities and by gender composition of the sibling pair, but, overall, sibling relationships in later life are not characterized primarily by the giving and receiving of social support, whether instrumental or expressive.

Symbolic functions of siblings. Despite the relatively infrequent rates of sibling contact or social support, most older adults report feeling very close to their siblings. Feelings of closeness have a cognitive (symbolic) component based on a shared past. Siblings are likely to share values, goals, and knowledge domains based on generational commonalities, such as fads or sociopolitical and historical events. Unlike friends, however, they also share early memories, which allows them to know each others personal references. As peers, siblings are unique family members throughout life, because they have the potential to share ideas and experiences more openly than parents and children who may be inhibited in some domains by generational barriers.

Siblings also serve as a special kind of attachment figure to one another in later life. Although their physical presence may not be sought frequently, most older adults sincerely believe that a sibling would come to their aid in a crisis, regardless of whether they get along well. In this way, siblings provide a safety net that, although rarely mobilized, provides a sense of security.

Factors affecting sibling relationships

The relationship between twins in late life is being studied for the first time. Such studies may reveal whether genes, environment, or both contribute to the quality of sibling relationships in late life. Because both identical and fraternal twins have more contact, provide more support, live closer, and feel emotionally closer than other siblings, it appears that the early environment has some kind of influence on the late-life relationship. By virtue of being born at the same time, both kinds of twins have more in common, such as more shared experiences early in life, than other siblings. But genes also play a role in the late-life relationship. For identical twins, satisfaction with the relationship and attachment security are completely independent of contact with the sibling, but this is not the case with fraternal twins, who have no more genes in common than any other siblings. (Neyer).

Race appears to have some influence on late-life sibling relationships. Compared to non-Hispanic whites, blacks tend to live nearer to their siblings, they tend to have more contact with siblings who live nearby, and they report that they provide more emotional support to their siblings. Race does not appear to influence instrumental support exchanges, however.

The general pattern of low social support from siblings in later life changes when a spouse, adult child, or other close relative is unavailable or nonexistent. For instance, feelings of closeness to a sibling and confiding in a sibling increase in the absence of other core family members. This substitution function of siblings becomes increasingly likely in very old age, particularly for women. While 53 percent of very old men (over age eighty-four, community-dwelling, and white) have a living spouse, only 9 percent of comparable women have a spouse. The increased divorce rate, the higher rate of childlessness, and the reduced fertility of younger cohorts are likely to result in a greater reliance on siblings for informal support in later years, compared to previous cohorts.

Gender also seems to influence sibling closeness. Sister dyads tend to be the most intimate, but there is less agreement on which combination of siblings is more intimate, sister-brother or brother dyads. Men are less likely than women to reveal their feelings toward siblings, but they may, nonetheless, hold sentiments of value and affection as deeply as women do.

Victoria Hilkeuitch Bedford

See also Intergenerational Support; Kin; Social Support.


Bank, S. P., and Kahn, M. D. The Sibling Bond. New York: Basic Books, 1997.

Bedford, V. H. Sibling Relationships in Middle Adulthood and Old Age. In Handbook on Aging and the Family. Edited by R. Blieszner and V. H. Bedford. Westport, Conn.: Greenwood, Press, 1995. Pages 201222.

Bedford, V. H. Sibling Interdependence in Adulthood and Old Age. In Vision 2010: Families and Aging, vol. 3, no. 2. Edited by T. Brubaker. Minneapolis, Minn.: National Council on Family Relations, 1996. Pages 1819.

Bedford, V. H., and Avioli, P. S. Variations on Sibling Intimacy in Old Age. Generations 25 (2001): 3440.

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Connidis, I. A. Family Ties and Aging. Thousand Oaks, Calif.: Sage Publications, 2001.

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Connidis I. A., and Davies, L. Confidants and Companions in Later Life: The Place of Family and Friends. Journal of Gerontology 45 (1990): S141S149.

General Social Survey. Cumulative datafile. Available online at

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Hochschild, A. R. The Unexpected Community. Berkeley: University of California Press, 1973.

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White, L. K., and Riedmann, A. When the Brady Bunch Grows Up: Step/Half- and Full Sibling Relationships in Adulthood. Journal of Marriage and the Family 54 (1992b): 197208.

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Sibling Relationships

Sibling Relationships


Sibling relationships are the longest lasting relationships of most peoples lives, and about 85 percent of all people have at least one sibling. Studies by researchers such as Judy Dunn, Victor Cicirelli, Wyndol Furman, and Susan McHale have contributed to our understanding of how sibling relationships develop from early childhood to adulthood, and how siblings influence each other. Research has focused on four broad areas: development of the relationship across the life course, the links between sibling and other family relationships, the impact of siblings on individual health and well-being, and the ongoing discussion of why siblings are so different.

Sibling relationships begin the day the second child arrives, and sometimes even earlier as parents talk about the arrival of a new baby. Judy Dunn and Carol Kendrick (1982) used interviews and in-home observations of mothers, firstborns, and infant siblings to understand why some sibling pairs develop relationships that are warm and supportive while others develop relationships that are hostile and conflictual. Their research, along with other studies, finds that a positive sibling relationship is more likely to develop when parents include the firstborn child in care of the baby and when they talk about the new baby as a person with needs and feelings just like their big sister or brother. At the other end of the life span, researchers such as Victoria Bedford, Victor Cicirelli, and Ingrid Connidis have demonstrated that social support is an important function of sibling relationships in adulthood and that childhood rivalries can reemerge when siblings spend more time together as adults. More recently, research is growing on siblings during adolescence and early adulthood. For example, Katherine Jewsbury Conger, Chalandra M. Bryant, and Jennifer Meehan Brennom (2004) used observations of sibling interactions and information reported by siblings to explain the changing nature of the sibling relationship in adolescence and the implications for social support in adulthood.

Parents are clearly recognized as important figures in the lives of young children, but for many, siblings are also important. Older siblings play many roles as playmates, teachers, role models, advisors, therapists, friends, and even bossy babysitters. Younger siblings play complementary roles as playmates, students, advice seekers, competitors, friends, and unwilling participants in activities devised by helpful older siblings. In fact, studies of cultures around the world find that four- and five-year-old siblings in some societies begin teaching their younger siblings as early as two and three years of age about language and proper behavior (Zukow 1989). Thomas S. Weisner (1989) presents a theoretical framework that takes family relationships and culture into account in explaining the unique contribution of siblings to social, emotional, and cognitive development. Cicirelli (1995) provides a comprehensive review of the varied theoretical and methodological approaches that researchers have used to study the association between parent-child and sibling relationships and the link between sibling relationships and those with friends and classmates. Laurie F. Kramer and Amanda K. Kowal (2005) report that positive behaviors between firstborns and their friends in early childhood are related to positive relationships with their younger siblings in childhood and early adolescence. Kramers research on resolving conflict between siblings will be of particular interest to parents.

The parents marital relationship is another important factor in the lives of siblings. Research by Clare Stocker and others reports that spousal conflict is related to conflict between siblings and can interfere with siblings ability to develop a positive relationship. Other research finds that some siblings bond more closely during difficult times such as a divorce or death of a parent. And research on stepfamilies finds that sibling relationships often suffer when parents divorce and remarry. Remarriage also adds the complexity of half-siblings and step-siblings.

Evidence is accumulating that siblings can promote competent behaviors as well as encourage problem behaviors. A special issue of the Journal of Family Psychology (December 2005) was devoted to research on siblings, and the studies demonstrate the exciting new advances made in this area. The editors, Laurie Kramer and Lew Bank, selected eighteen articles designed to illustrate the ways in which sibling relationships serve as important contexts for both individual development and family functioning (p. 483). Many of the studies use sophisticated statistical analyses that allow social scientists to examine sibling relationships within families across multiple points in time. These studies, conducted with a broad range of ethnically diverse families, demonstrate the increased appreciation for the importance of siblings roles in family life and individual development. Interested readers will also want to refer to Frits Boer and Judy Dunns 1992 book, Childrens Sibling Relationships: Developmental and Clinical Issues, which provides a summary of clinical and developmental issues, including the impact of a siblings illness or disability on individual development and sibling relationships.

One frequently asked question is why siblings are so different if they grew up in the same family. The ongoing debate centers on nature (a persons genetic makeup) and nurture (shared and nonshared experiences in the family such as parenting and other social settings). The field of behavior genetics uses comparisons between twins, full siblings, and adoptive siblings to explain individual similarities and differences in personality and behavior (Dunn and Plomin 1990; Lytton and Gallagher 2002). One example illustrates why there are no easy answers to this ongoing debate. Everyone can understand why identical twins (monozygotic, or conceived with one egg) are similar because they share 100 percent of their genetic material, so if differences are observed they are the result of the environment such as experiences with parents and friends. However, their environment also is likely to be more similar because these twins are the same sex and arrive at the same time in the family. Fraternal twins (dyzygotic, or conceived with two eggs) also arrive in the family at the same time but share only about 50 percent of their genes and they may be the same or opposite sex. For these siblings, some factors are pushing them toward similarity and others toward difference. Full siblings (the most common variety) also share about 50 percent of their genetic material, but each sibling arrives at a different point in the familys life. Even though they all live in the same family, the experiences of one sister may be quite different from those of her sister or brother.

Differential parental treatment has been identified as one factor that explains why siblings in the same family might be so different (McGuire 2001). Parents, and most children, agree that parents should treat siblings differently because of age, sex, temperament, and other individual characteristics. However, if parents play favorites and the siblings feel the treatment is unfair, then there can be negative consequences. Several researchers (e.g., Gene Brody, Katherine Conger, Shirley McGuire, Susan McHale, and Robert Plomin) have found that differential parental treatment may be related to negative relations between siblings, child behavior problems, and conflictual family relations. Moreover, siblings can also influence the parenting behaviors. The exploration of shared and non-shared environments as explanations for sibling similarities and differences continues to be a promising area for research.

SEE ALSO Child Development; Children; Determinism, Biological; Determinism, Environmental; Family; Family Structure; Heredity; IQ Controversy; Marriage; Nature vs. Nurture; Parenting Styles; Twin Studies


Boer, Frits, and Judy Dunn, eds. 1992. Childrens Sibling Relationships: Developmental and Clinical Issues. Hillsdale, NJ: Erlbaum.

Brody, Gene H., ed. 1996. Sibling Relationships: Their Causes and Consequences. Norwood, NJ: Ablex Publishing.

Cicirelli, Victor G., ed. 1995. Sibling Relationships across the Lifespan. New York: Plenum Press.

Conger, Katherine Jewsbury, and Rand D. Conger. 1994. Differential Parental Treatment and Change in Sibling Differences in Delinquency. Journal of Family Psychology 8 (3): 287-302.

Conger, Katherine Jewsbury, Chalandra M. Bryant, and Jennifer Meehan Brennom. 2004. The Changing Nature of Adolescent Sibling Relationships: A Theoretical Framework for Evaluating the Role of Relationship Quality. In Continuity and Change in Family Relations: Theory, Methods, and Empirical Findings, eds. Rand D. Conger, Frederick O. Lorenz, and K. A. S. Wickrama, 319-344. Mahwah, NJ: Erlbaum.

Dunn, Judy, and Carol Kendrick. 1982. Siblings: Love, Envy, and Understanding. Cambridge, MA: Harvard University Press.

Dunn, Judy, and Robert Plomin. 1990. Separate Lives: Why Siblings Are So Different. New York: Basic Books.

Furman, Wyndol, and Richard Lanthier. 2002. Parenting Siblings. In Handbook of Parenting, 2nd ed. Vol. 1: Children and Parenting, ed. Marc H. Bornstein, 165-188. Mahwah, NJ: Erlbaum.

Kramer, Laurie F., and Lew Bank, eds. 2005. Sibling Relationship Contributions to Individual and Family Well-Being: Introduction to the Special Issue. Journal of Family Psychology 19 (4): 483485.

Kramer, Laurie F., and Amanda K. Kowal. 2005. Sibling Relationship Quality from Birth to Adolescence: The Enduring Contributions of Friends. Journal of Family Psychology 19 (4): 503511.

Lytton, Hugh, and Lin Gallagher. 2002. Parenting Twins and the Genetics of Parenting. In Handbook of Parenting, vol. 1: Children and Parenting, ed. Marc H. Bornstein, 227253. Mahwah, NJ: Erlbaum.

McGuire, Shirley. 2001. Nonshared Environment Research: What Is It and Where Is It Going? Marriage and Family Review 33 (1): 3156.

Weisner, Thomas S. 1989. Comparing Sibling Relationships across Cultures. In Sibling Interaction across Cultures: Theoretical and Methodological Issues, ed. Patricia Goldring Zukow. New York: Springer-Verlag.

Zukow, Patricia Goldring, ed. 1989. Sibling Interaction across Cultures: Theoretical and Methodological Issues. New York: Springer-Verlag.

Katherine Jewsbury Conger

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