Since you already collect child support, there is really nothing more that you can initiate. It is up to him to seek to legitimate the child and seek visitation. You cannot force him to do that. Until he does so, he has no legal rights to the child, and you are the sole custodial parent with all rights to decision making for the child. Of course, if he files anything at all, you need to retain an experienced custody attorney to protect those rights.
I am exclusively a family law attorney, practicing primarily in the metro Atlanta, Georgia trial courts. However, I handle appeals from anywhere in Georgia.
You ALREADY have sole custody. Until and unless he seeks to legitimate the child (and succeeds) he has no rights at all to teh child but does have a duty to pay support. As a general rule, unless you get married and a future spouse wants to adopt the child, he cannot "sign over his rights."
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Because your son's father has not legitimated the child and was not born to you, by operation of law, you are the child's only legal parent and have sole custody. You don't need to do anything at all. The father is obligated to pay child support, and you should faithfully follow up with Child Support Services at any time he stops paying.
He has zero visitation rights whatsoever, so he is not entitled to see your son at all unless you allow it. It sounds like the problem though is that you WANT him to have a relationship with his son, and he really wants to pretend the whole thing never happened (understandable if he's married). You might want to redirect your efforts toward making sure that your son has positive male role models around and other family members around to care for and support him.
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