Permissibility/Limits of Disciplining Grown Children

Is it permissible for parents to hit their daughters especially mothers?
daughters are in the 30s and unmarried.
is it permissible for a mother to give other people and her nieces etc more importance over her own child?
is it permissible for mother to talk in a rude way not consider her own childs feelings and consider only hers or her nieces and other people.
please explain what is the ultimate ideal relationship of children with their mothers esp daughters?
Is it ok for a mother to be bitter with her marital relationship and vent this on the child? esp if the child tries to help even if it means going against the mother.