Abstract: In a social structure where traditional familism and individualization coexist, the intergenerational coparenting relationship in Chinese urban families shows complexity and ambivalent characteristics. As major actors in intergenerational coparenting, grandparents shape coparenting relationship through daily interactions, but the dynamics mechanism of the impact has not been fully examined. This study examines the impact of grandparents' authoritative resources at the economic, ethical, and psychological levels on different dimensions of intergenerational coparenting relationships. In addition, it explores the moderating effect of distinct intergenerational coparenting dyads on this influence. This study used the convenience sampling approach. The samples were taken from intergenerational coparenting families in Shanghai and Tianjin and analysed using multivariate linear regression model. The results show that grandparents' psychological control over parents is negatively associated with intergenerational coparenting relationships. In contrast, authoritative resources at the economic and ethical level only have positive associations with some specific dimensions of intergenerational coparenting relationships. Compared with mother-in-law and daughter-in-law coparenting, the relationship in mother and daughter coparenting combination is generally more positive. In different coparenting combinations, the impact of grandparents' authoritative resources on intergenerational coparenting relationships varies and shows a certain degree of complexity. Therefore, to improve cooperation and intimacy in intergenerational coparenting, grandparents need to develop authoritative resources with more cultural inclusiveness, and negotiate with parents over the balance between cultural tradition and individualized lifestyle.

Key words: intergenerational coparenting relationship, authoritative resource, psychological control, filial piety, intergenerational coparenting combination