What can I do if my grand daughter wants to live with me?

That is a complicated situation.  The general rule (and particularly after the U.S. Supreme Court's Troxel v. Granville decision) is that grandparents do not have standing to seek custody where the parents object.  If your granddaughter is the daughter of your son and your son is deceased, that might change the calculus and give you standing under the grandparent visitation statute.  But otherwise, courts may not infringe on parental rights in favor of grandparents. The next question is how old is your granddaughter?  The older the child, the more inclined courts are to take their wishes into consideration.  That, too, however, may not be relevant in a contest between a grandparent and a parent (only between parents). It is for situations such as this that the Uniform Law Commission promulgated the Uniform Non-parent Custody and Visitation Act.  Had New York adopted that set of proposed laws, you might have standing to challenge your daughter[-in-law] for custody.  Without it, however, you have an uphill battle because, generally, grandparents lack "standing" to challenge a parent. The specifics of your case might give you further rights.  For example, you don't say how long you've been caring for your granddaughter.  You don't say what contact her mother has had with her during this time. So possibly with better knowledge of the facts a claim can be made successfully.  But the simple answer, unfortunately, is no, you can't prevail in a legal contest with your granddaughter's mother. Good luck and God bless for the good your doing. Chaim.