Middle-class children, divided by age, sex, and the presence/absence of younger siblings in the family, were studied to assess their interest in babies. The findings support MacDonald's contention that birth order effects are best understood as distinctive for each sex, especially when the behaviors investigated are sex-related. (Author/GC)

This study was designed to investigate male and female interest in babies at middle childhood and adolescence. A total of 64 middle class subjects (half 8- to 9-years-olds, half 14- to 15-year-olds) were observed individually in a 6-minute waiting room situation with an unfamiliar 6- to 10-month-old baby and mother (confederate). While the subject…