Grandparents rights vary from state to state. In WA, where I live, Grandparents have no rights, per se. If the parents are in the picture, the grandparents have no rights to sue for visitation. So, my ex DH's parents can't sue him or me b/c they don't see the grandkids as often as they used to when we were married. Some states do allow grandparents to sue for visitation. Check your state laws for each state.
If the parents are not acting in the best interest of the child & the child is removed from the home or the parents lose their rights, the grandparents are usually a logical choice for custodians. Not always, but many times if a child cannot live with their parents, the courts will look for a relative. If the grandparents are given temporary custody, they have more of a legal leg to stand on to obtain permanent custody or visitation after the child returns to the parents.
Please share more if you need more!
at 12:26 AM on Aug. 1, 2009