who needs to sign rights over

I think it is only the parents. My aunt tried to talk her daughter and ex sil into let them (grandparents) to have custody on their grandson. Mom said yes and signed but the sil changed his mind. They do raise the little boy. Anyway my point is for custody I think it is just the parents.

Only the parents would have to sign over rights, but the other gparents may be able to petition for adoption as this is a family situation.