This paper examines the effect of birth order and family size on human capital using a consistent measure of cognitive … that is orthogonal to family size, as well as controlling for student and family covariates, we find negative family size … no evidence of a relationship between birth order effects and the level of development, while the effect of family size …

for heterogeneous effects by degree of prematurity, as well as whether family socioeconomic resources and school … effects on school grades, but these negative effects are largely confined to children born extremely preterm (<28 weeks of … gestation, i.e. born at least 10 weeks earlier). Children born moderately preterm (i.e. born up to 5 weeks early) suffer no ill …