摘要：This paper describes the relation between fertility and intergenerational child-care support provided by grandparents in a model based on the overlapping generations model with endogenous fertility. Results show that intergenerational child-care support causes fertility to fluctuate. This paper presents an alternative model of fluctuating fertility shown by the `Easterlin Hypothesis' described by Benhabib and Nishimura (1989), and others. Moreover, this paper shows that an increase in rewards for child care supplied by older people does not always increase child care. Consequently, younger people can not depend on sufficient intergenerational child-care support
