Legal Question in Family Law in Pennsylvania

I am not sure what your mother signed. Generally one cannot sign away support rights. In adoption situations a person ie" your father can voluntarily relinquish parental rights if your mother had you adopted by a step parent. It does not seem that any of this happened from these facts. If your "father" has a will and does not mention you it is possible you would not be able to claim an interest. Of course if he specificall mentioned your name and indicated he was not leaving you anything he would have a much stronger case. If he dies without a will you can claim to take against his estate as a child but you would have to prove your relationship. ie birth certificate or some other means to establish your being his blood child.