This longitudinal study examines the association between child gender and child aggression via parents’ physical control, moderated by parents’ gender‐role stereotypes in a sample of 299 two‐parent families with a 3‐year‐old child in the Netherlands. Fathers with strong stereotypical gender‐role attitudes and mothers were observed to use more physical control strategies with boys than with girls, whereas fathers with strong counterstereotypical attitudes toward gender roles used more physical control with girls than with boys. Moreover, when fathers had strong attitudes toward gender roles (stereotypical or counterstereotypical), their differential treatment of boys and girls completely accounted for the gender differences in children's aggressive behavior a year later. Mothers’ gender‐differentiated parenting practices were unrelated to gender differences in child aggression.