We investigate how fertility and demographic factors affect migration at the household level by assessing the causal effects of sibship size and structure on offspring's international migration. We use a rich demographic survey on the population of Mexico and exploit presumably exogenous variation in family size induced by biological fertility and infertility shocks. We further exploit cross-sibling differences to identify birth order, sibling-sex, and sibling-age composition effects on migration. We find that large families per se do not boost offspring out-migration. Yet, the likelihood of migrating is not equally distributed within a household, but is higher for sons and decreases sharply with birth order. The female migration disadvantage also varies with sibling composition by age and gender.
International Migration Mexico Family Size Sibling Structure