Research shows that over-education has negative effects on individuals in terms of their wage and job satisfaction. In this paper, we study the intergenerational implications of over-education via childcare time. We analyze whether being over-educated affects the time mothers devote to take care of their children. We use the American Time Use Survey from 2004 to 2017. We find that over-educated mothers devote less time to primary childcare than they would do were they matched. The effect of being a college graduate mother on primary childcare time during weekdays is significantly lower when she is over-educated. Results suggest that being over-educated is not a deliberate choice prioritizing family over career.