Does the child penalty strike twice?

This paper compares the labor market trajectories of grandparents before and after the arrival of their first grandchild. We find gender gaps in earnings of 4 and 10 percent five and ten years, respectively, after the first grandchild. These effects are driven by changes in women's labor supply at both the intensive and extensive margin. We provide evidence from multiple data sources that grandmothers’ caregiving complements formal daycare, thereby offering essential flexibility for young parents. We document that grandchild penalties were larger in earlier periods characterized by low availability of daycare, shorter parental leave, and an earlier retirement age. Linking register data to geographical variations in daycare centers reveals that local daycare coverage is not associated with grandchild penalties. Detailed time use data show that grandmothers carry larger responsibilities for childcare than grandfathers. Recognizing the complementary nature of grandmaternal childcare is important for the design of policies attempting to reduce child penalties for both mothers and grandmothers.