You can fight this battle on grounds of "psychological" parenthood with his voluntary actions however you are best suited at least consulting with an attorney.
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Sorry to tell you but he can insist upon a DNA test of you and the child to see if he is the natural father of the child. Of course, if you know she is his daughter, then the DNA test should be of little concern to you since it will also shut up the new wife and prove unquestionably that she is your daughter with him. Once the test is done, that's the end of the entire matter. Only you know one way or the other and I suggest you submit to it and get it behind you.
By the way, even with DNA claiming that someone is the father, I've seen it defeated by a good lawyer.
If the father raises the issue he has the right to a DNA test. I know it can be very tough on a child however you can just blame it on the court . However, if he has "affirmed " his fatherhood in the court he may be barred from now taking a different position . This approach however will need an attorney to sort through the facts.
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