Sibling Relationships

their Nature and Significance Across the Lifespan

M. E. Lamb, B. Sutton-Smith, Brian Sutton-Smith, Michael E. Lamb

• Publisher: Psychology Press
• Year: 2014
• ISBN:
  9781317769576
• Edition: 1
• Topic: Psychologie
• Subtopic: Geschichte & Theorie in der Psychologie

First published in 1982. Since the emergence of developmental psychology early this century, theorists and researchers have emphasized the family's role in shaping the child's emergent social style, personality, and cognitive competence. In so doing, however, psychologists have implicitly adopted a fairly idiosyncratic definition of the family— one that focuses almost exclusively on parents and mostly on mothers. The realization that most families contain two parents and at least two children has occurred slowly, and has brought with it recognition that children develop in the context of a diverse network of social relationships within which each person may affect every other both directly (through their interactions) and indirectly (i.e., through A 's effect on B, who in turn influences C). The family is such a social network, itself embedded in a broader network of relations with neighbors, relatives, and social institutions. Within the family, relationships among siblings have received little attention until fairly recently. In this volume, the goal is to review the existing empirical and theoretical literature concerning the nature and importance of sibling relationships.

1 Sibling Relationships Across the Lifespan: An Overview and Introduction

Michael E. Lamb
University of Utah

Overview

More than a decade ago, Brian Sutton-Smith and Ben Rosenberg published a book entitled The sibling (1970). In this book, they summarized the results of research, much of it conducted by the authors themselves, on the effects of birth order and sibling status on personality and intellectual development. By the time the book was written, the accumulated evidence was impressive, but somewhat paradoxically, publication was associated with (if not causally related to) a temporary decrease in the amount of attention paid by researchers to sibling relationships and effects. The publication of the present volume, replete with chapters containing recent findings and the description of ongoing studies, testifies to the current resurgence of interest in sibling relationships and their formative significance. There are, however, several important differences between the research on sibling relationships conducted decades ago and the type of research that is now gaining popularity. These differences involve: a) a shift from the study of effects to the study of formative processes; b) the appreciation of cultural variability and the need to consider inter- and intraspecies diversity and similarity; and c) the growing concern with development across the lifespan, rather than only in childhood. Let us consider each of these issues in turn.

From Effects to Process

Whereas researchers were formerly concerned with the identification of sibling status effects, contemporaiy researchers are eager to determine the processes whereby effects are mediated. In the earlier work, the focus was on the effects of sibling status on personality and intellectual development, and the methodology adopted was very straightforward. Large numbers of people (usually high school or college students) were tested on standardized measures of some aspect of psychological or cognitive functioning. Groups of subjects differing with respect to sibling status were then compared, and any differences among the groups were attributed to sibling status. Since the research was exclusively correlational in nature, researchers could only speculate about the formative processes that had led to the emergence of the demonstrated group differences. Was it the behavior of older sisters that made younger brothers more cognitively competent, or did parents behave differently when they had an older daughter and a younger son? Did the enhanced masculinity of second-born boys with older brothers occur because the youngsters had additional male models with whom to identify, because the older brother and his predominantly male friends teased the youngster whenever he behaved "like a sissy" and offered only male-typed activities for him to observe and/or engage in, because fathers (as adult role models) were especially salient and involved when they only had sons, or because parents could enforce clearer standards regarding sex-typed behavior when they only had children of one sex? It is clearly essential that developmental psychologists address questions regarding formative processes and that they evaluate the relative explanatory power of the competing hypotheses raised by studies of sibling status effects. Unfortunately, the retrospective correlational strategy is not adequate for this task, and this has led to a change in the research strategies employed in studies of sibling relationships.

The new generation of research on sibling relationships is descriptive and process oriented. Many of the recent studies involve observational analyses of family and sibling interaction designed to determine how the effects revealed in studies of sibling status may have arisen (see, for example, the chapters by Nadelman and Begun, Dunn and Kendrick, Abramovitch, Pepler, and Corter, and Cicirelli). This is not to say that group difference studies are passe; on the contrary, several of the contributors to this volume rely heavily upon this strategy. However, researchers and theorists can now refer to a rapidly growing body of research focused on the elucidation of processes, and there is a general awareness that sibling status comparison studies can never in themselves demonstrate formative processes. Both group difference studies and process-oriented studies are informative, and the integration of these complementary strategies promises to advance understanding faster than exclusive reliance upon either one. Appreciation of the need to employ multiple research strategies is a distinctive feature of contemporary research on sibling relationships, which is amply reflected by the thoughtful contributions to the present volume.

Biological Influences and Intraspecies Variability

Current research on sibling relationships also reflects a growing awareness throughout the developmental sciences that we must look beyond the socialization practices of modern western cultures if we are to attain a satisfactory and generalized understanding of formative developmental processes. Consequently, attempts have been made to identify species-typical patterns by studying intercultural consistencies and variations, and to identify biological constraints by intraspecies, interspecies, and behavior-genetic comparisons. Comparative anthropologists proceed by describing intraspecies variations and universals, comparative psychologists examine interspecies similarities and differences, while behavior geneticists attempt to quantify the relative contributions of heredity and environment by comparing similarities among people of varying degrees of relatedness to one another. Several of the chapters in the present volume exemplify the utility of these approaches. The chapter by Weisner focuses on sibling relationships in nonwestern societies, bringing to bear the interpretative framework of contemporary comparative anthropology. Weisner contends that one can obtain a broader and clearer understanding of sibling influences in any given culture by contrasting the behavior of siblings in that culture with their behavior in a variety of comparison cultures. Another chapter (that by Suomi) focuses on sibling relationships in nonhuman primates and exemplifies the perspective of comparative psychology in the course of building an animal model of sibling influences and relationships. Suomi believes that we can facilitate the understanding of sibling relationships and influences within our species by examining other, closely related species. He proposes that general biological and sociobiological principles are best understood by studying and comparing a variety of species facing diverse ecological challenges. Furthermore, it is possible to conduct experimental studies involving other species that would be ethically and practically impossible to attempt with humans.

Yet another perspective is offered by Scarr and Grajek, who review behavior genetic evidence suggesting that some similarities and differences among siblings must be attributed (respectively) to their shared and different genetic endowment. They note, quite appropriately, that in their single-minded focus on socially-mediated influences, developmental psychologists often lose sight of the fact that siblings share 50% of their genes. Consequently, many similarities among siblings may be genetically based, and Scarr and Grajek review evidence supporting this hypothesis. More provocatively, they argue that genetic differences between siblings help create different environments that exaggerate the phenotypic expression of these differences.

The Lifespan Perspective

A third perspectival change in the study of sibling relationships, again one which reflects a general trend in the study of development, has to do with a shift from a focus on children to a focus on people of all ages. Only recently, upon the insistence of lifespan developmental theorists, have psychologists become interested in development across the lifespan. For the most part, lifespan developmental psychologists have focused on methodological issues, or on the formative significance of "critical events" that take place in adulthood (e.g., marriage, parenthood, divorce, and various stages on the career trajectory). Compared with the "critical events" of interest to many lifespan developmental psychologists, family relationships are distinctive in that they themselves last over large portions of the lifespan—from childhood through adulthood. Unlike parent-child relationships, furthermore, sibling relationships are not predictably terminated by the death of one party while the other is still relatively young. Instead, sibling relationships often last an entire lifetime. Several of the contributions to this volume focus on this issue. In some chapters, the focus is on the preservation and perceived importance of the relationships among adult siblings (e.g., Bank & Kahn, Ross & Milgram, Cicirelli). In other chapters, the focus is on the extent to which sibling status effects are evident beyond adulthood (e.g., Rosenberg, Cicirelli). Whether these effects have their origins in earlier or contemporaneous interactions remains to be determined.

The emergence of lifespan developmental psychology has not only meant that adults must now be viewed developmentally; a broader change in perspective has occurred. The lifespan view proposes that development is continuous, with individuals continually adjusting to the competing demands of socialization agents and endogenous tendencies. Thus, even those concerned only with interactions among young siblings implicitly or explicitly acknowledge that all relationships change over time and that any "effects" may be eliminated, reinforced, or altered by later experiences. Thanks to the growing significance of lifespan theory, developmental psychology is currently witnessing a shift from emphasis on the long-term consequences of early experiences to a dynamic interactionist lifespan view. As the contents of the volume make abundantly clear, this revolution has had a marked impact on the study of sibling relationships.

Siblings as Agents of Socialization

None of the classical theories of personality or of psychological development portrayed siblings as important agents of socialization. Traditionally, psychological theories have emphasized parental influences on child development. (Parsons' theory [Parson & Bales, 1955] was, of course, an exception but it has always been of greater interest to sociologists than to psychologists.) However, a broader and more inclusive view of socializing agents has characterized the latest era of research on socialization and personality development (Zigler, Lamb, & Child, 1982), and in a recent review Belsky (1981) argued for the convergence of developmental psychology and family sociology. Besides parents, most attention has been focused on teachers and peers, but there has also emerged an appreciation that families are complex social systems, comprising a network of relationships within which each individual has the potential to influence every other member both directly and indirectly (i.e., mediated via the impact on third parties). However, most discussions of family influences still focus on the mother-father-child triad rather than four- and five-person families. As a result, an appreciation of the potential importance of sibling relationships has developed slowly.

Demographic statistics demonstrate that most children grow up with siblings. Even though the average family size has dropped in most western countries from the extreme fecundity of the "baby boom" that followed World War II, the modal family today contains two children, and a declining proportion contain three or more. The ubiquity of siblings and sibling relationships does not guarantee that siblings are of formative significance, of course, but it does necessitate attempts to determine just how influential they are.

Sibling influences begin even before the second child is born, for the anticipation of the youngster's birth affects the parents as well as their relationships with and availability to their first-born offspring. The subsequent arrival of the new baby further accentuates these effects (see Nadelman & Begun, chapter 2; Dunn & Kendrick, chapter 3). Usurpation of the first-born's unique status in the family sets the stage for resentment and rivalry, but although conflict between siblings is frequent, it usually occurs in the context of generally positive relationships between siblings. Among home-reared children, siblings are the most regular— often the only regular—playmates available to both older and younger siblings, and for the younger members of sibling pairs, older brothers and sisters are the primary models of interesting childlike activities (Lamb, 1978; Abramovitch, Pepler & Corter, chapter 4). When both parents are employed, siblings are likely to be placed with the same supplementary caretaker; although their social network is thus extended to include other children, the siblings' relationship is not disrupted.

Commonly, the first major threat to the sibling relationship occurs when the children enter the public school system—an institution that is notable for its extreme emphasis on age segregation. Nevertheless, as Ellis, Rogoff, and Cromer (1981) have shown recently, children regularly associate with both age-mates and non-age-mates outside school and so sibling relationships are not necessarily disrupted by schooling. Older children are increasingly likely to be given temporary responsibility over their siblings once they reach school age, and in nonwestem cultures, primary caretaking roles are often assumed by preadolescent siblings (Weisner & Gallimore, 1977). Younger children, meanwhile, increasingly find themselves being compared to their older siblings by teachers as well as by parents and relatives. Although these repeated comparisons may elicit attempts to differentiate between oneself and one's siblings in order to assert one's individuality, this individuation seldom occurs at the expense of the sibling relationship. On the contrary: siblings commonly become primary confidantes and sources of emotional support in preadolescence, and these mutually important relationships usually persist well into adolescence and young adulthood. During adolescence, when parents and children often have difficulty communicating about emotionally laden issues such as sexuality and the use of recreational drugs, and friends of both sexes prove fickle and unpredictable, siblings provide the most reliable and consistently supportive relationships. Sibling relationships may lose their urgent and unique importance in adulthood, although many young adults continue to find it easier to talk to siblings than to parents. In any event, as several contributors to the present volume demonstrate, it is not unusual for siblings to remain sources of emotional support, advice, and companionship into adulthood.

In contrast with the practices of the many cultures discussed by Weisner (chapter 13), modern western societies seldom assign specific roles in the socialization process to siblings. Wittingly or unwittingly, however, the evidence suggests that their influence is often profound. Siblings set and maintain standards, provide models to emulate and advice to consider, enact complementary roles in relation to one another through which both develop and practice socialinteractional skills, and serve as confidantes and sources of nonjudgmental social support in times of emotional stress (e.g., break-ups with steady dates, menarche, pregnancy scares, etc.). Sibling relationships retain these qualities into adulthood, whereas parent-child relationships often retain a nonegalitarian and judgmental quality long after the children attain adulthood or parenthood themselves. Finally, besides marital relationships, sibling relationships are often the only heterosexual relationships in which western adults can express affection and closeness without eliciting disapprobation and gossip. Heterosexual sibling relationships may be especially important in adolescence and early adulthood, when long-term sexual commitments are commonly explored for the first time.

Outline of the Volume

The chapters in this volume can be classified into four groups on the basis of their contents. The first and largest group (chapters 2 to 11) consists of chapters focused on the nature and significance of sibling relationships at specific points in the lifespan. These ten chapters are organized in rough chronological sequence, beginning with two chapters concerned with the effects of a second child's birth on existing family relationships, and ending with discussions of sibling relationships in mid- to late adulthood. There follows, in the brief second section, a single chapter concerned with children and adults who do not have siblings. The third set of chapters comprises various alternatives to the narrow perspective on sibling relationships that is obtained when we focus exclusively on western societies. This section includes contributions by a comparative anthropologist, a comparative psychologist, and two behavior geneticists. The book closes with a reflective epilogue written by one of the editors.

A Chronological Sequence

Chapters 2 through 11 form a chronological sequence; they are organized roughly by the age of the siblings who are the focus of the authors' research and speculation. Thus in the first chapter in this sequence, Nadelman and Begu...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Preface
• List of Contributors
• 1. Sibling Relationships Across the Lifespan: An Overview and Introduction
• 2. The Effect of the Newborn on the Older Sibling: Mothers' Questionnaires
• 3. Siblings and Their Mothers: Developing Relationships Within the Family
• 4. Patterns of Sibling Interaction Among Preschool-age Children
• 5. Sibling Relationships in Middle Childhood
• 6. Sibling Deidentification and Split-Parent Identification: A Family Tetrad
• 7. Birth Order and Sibling Status Effects
• 8. Life Span Personality Stability in Sibling Status
• 9. Important Variables in Adult Sibling Relationships: A Qualitative Study
• 10. Intense Sibling Loyalties
• 11. Sibling Influence Throughout the Lifespan
• 12. Only Children in America
• 13. Sibling Interdependence and Child Caretaking: A Cross-Cultural View
• 14. Sibling Relationships in Nonhuman Primates
• 15. Similarities and Differences Among Siblings
• Epilogue: Framing the Problem
• Author Index
• Subject Index