BIRTH-ORDER AND AGE-DIFFERENCES IN EARLY SIBLING ROLES

Seventy-six two-children families were assigned to one of three cohort s that differed in the second born's age at an initial home visit (5, 11, or 17 months); the families were seen again 6 months later, when t he baby was 11, 17, or 23 months. Mothers rated each child on nine sib ling role qualities (i.e., functions or feelings) that reflect aspects of sibling roles. Children were also videotaped interacting in struct ured situations that were later coded for specific functions. First an d second borns were seen to fulfill different roles; e.g., mothers rat ed firstborns lower than second borns on identification, but higher on help. The differences between the two children on some aspects of sib ling roles (e.g., identification) did not change with the children's a ges. Yet other aspects (e.g., help) became increasingly similar, and s uch changes were attributable to the baby's development. Children's be haviour in the structured situations also changed over the early sibli ng relationship, but, although some changes were attributable to the b aby growing older, others were attributable to the older sibling's, or to both children's, development. The discussion focuses on possible s ources of birth order and age differences in early sibling roles.