The gender gap within families regarding access to educational resources is an important social determinant of gender inequality. Contradicting the conventional “preferring sons to daughters” model of household resource allocation, many studies find that Chinese families nowadays prefer to invest in girls’ after-school education. This study focuses on this empirical fact that has not been examined in depth previously, and attempts to explore its key influence mechanisms. Starting from the theoretical context of intergenerational resource allocation, the article suggests two explanatory hypotheses – “change in family gender preferences” and “divergence between mothers’ and fathers’ gender preferences” – in the analysis of the succession of intergenerational preference patterns. An analysis of the China Education Panel Survey (2013–2014) data on families with male siblings and parents with different education levels is conducted. The statistical results show robustly that the presence of brothers in the family does not negatively impact girls’ access to after-school education, that in urban families girls have a pronounced advantage over boys, and that, overall, there has been a tentative shift from “son preference” to “daughter preference” in Chinese families. In addition, under reciprocal controls, the father's increased education has no significant effect on children but a significant positive effect of the mother's increased education is observed on girls’ access to after-school education, and the latter effect is even more pronounced among younger parents, exhibiting a clear pattern of “dual preferences”. These findings, at the empirical level, reveal that the increased family utility of girls compared to boys and the enhanced status of mothers in the process of social change have driven a shift in the logic of family gender preferences.