Despite evidence that infants affect families' economic and social behaviors, little is known about how young children influence their parents' political engagement. I show that U.S. women with an infant during an election year are 3.5 percentage points less likely to vote than women without children; men with an infant are 2.2 percentage points less likely to vote. Suggesting that this effect may be causal, I find no significant decreases in turnout the year before parents have an infant. Using a triple-difference approach, I then show that universal vote-by-mail systems mitigate the negative association between infants and mothers' turnout.