Married daughters have the obligation to support their parents. Children's obligation to support their parents is legal and has nothing to do with whether their children are married or not. When parents are old, they have the right to ask adult children to pay alimony on time and fulfill their legal obligations. If the child does not pay alimony, the parents can solve it through litigation, and they can bring an alimony lawsuit to the people's court, and the people's court will make a judgment according to law. Both parents' children have no ability to support, but grandchildren can be required to bear the obligation to support if they have the ability.

People's Republic of China (PRC) Civil Code

Article 1071 Children born out of wedlock enjoy the same rights as children born in wedlock, and no organization or individual may harm or discriminate against them.

The biological father or mother who does not directly raise children born out of wedlock shall bear the responsibility for raising minor children or adult children who cannot live independently.

Article 1074. Grandparents who can afford it have the obligation to support their minor grandchildren whose parents are dead or unable to support them.

Grandchildren and grandchildren with financial means have the obligation to support grandparents whose children have died or whose children are unable to support them.