Drawing on two data sources from across Europe, we show that both bequest motives of parents and children’s gender composition shape unequal divisions of bequests. First, the Survey on Health, Ageing and Retirement in Europe reveals that observed bequests are divided unequally when children differ in sex, caregiving, or income, with bequest motives strongest among mixed-sex children. Second, in a vignette experiment featuring alternative bequest motive scenarios and randomised gender compositions for two fictitious children, hypothetical bequests are most unequally divided under the exchange motive while children’s gender composition matters more under the altruistic motive. Fictitious parents favour daughters regardless of deservingness, granting the highest bequest share to a deserving daughter with a brother. In return, these patterns reinforce traditional gender norms.