Are Brothers Really Better? Sibling Sex Composition and Educational Achievement Revisited

In this paper, I examine the relationship between sibling sex composition and educational achievement. First, I replicate the study of Butcher and Case (1994) using data on a more recent birth cohort. Contrary to the findings of that study, I find basically no effect of sibling sex composition on the educational attainment of white males or females, although among black adults, those who grew up with a sister, or who had relatively more sisters, had greater levels of educational attainment than persons with no or fewer sisters. Second, I broaden the analysis by examining the educational outcomes of children and teenagers. This extension is important because it provides an additional opportunity to test for sibling sex composition effects, and it helps differentiate between potential causes of a sibling sex composition effect. The results obtained from the analysis of child and teen outcomes suggest that sibling sex composition had little effect on educational achievement. The only group to be affected was black teens between the ages of 15 and 18. Those who grew up with sisters had higher educational achievement levels than those who grew up with brothers.