In a pro-male biased society, brothers may reduce the parental investment received by female siblings, if parents face time or financial constraints. But brothers may also cause positive externalities. Using more than 12,000 firstborn twins from a highly sex-imbalanced economy, Taiwan, we test...

Son-preferring parents tend to continue to have babies until a son's birth. After deciding the set of children, the parents with resource constraints may divert family sources from daughters to a son. Thus, the presence of a son, relative to a daughter, have 2 distinct effects on his sister's...