This article uses the cross-sectional data of Chinese Family Panel Studies of 2016 to analyze the impact of elderly parents' housework support on the second-child birth status of their children's families. The results of the study show that: First of all, helping elderly parents with housework will significantly increase the fertility rate of the second child in their children’s family by 4.9%, and the instrumental variable retest coefficient will increase to 7%, which is robust. Secondly, the intergenerational housework support provided by elderly parents has a greater impact on the second childbirth of the son’s family than the daughter. Finally, the impact of intergenerational housework support in rural families on children having a second child is greater than that in urban families. The article verifies the family value of the elderly from the perspective that intergenerational housework support affects the fertility status of the second child's family, and also explains from the side that the intergenerational support provided by the elderly is an effective way to increase fertility.