To offer another point of view on this whole (potential) mess--which yes, could be very messy indeed:
If you are not married and not therefore seeking divorce, and you are already the child's primary caregiver, then just go on with your life and DO NOT ASK BIODAD FOR MONEY.
Mind you, I am not saying that you should forgo child support! I'm saying, YOU should not ask biodad for money. Simply seek recourse in the Child Support Enforcement agency of your residential state. Let that agency handle this matter, and you should probably avoid discussing it with biodad. Don't even tell him you've called CH.Support, just drop it. There is no reason to discuss it with him since the State will handle ch. support in accordance, after all, with laws regarding ch. sup....and there's really nothing you can do about that. Child Support is the Law. Period. He will have to deal with that on his own.
If this Difficult Man (and hehehehe, I think I know his 'twin brother'

), once approached by the State for child support, chooses to attempt to get custody, THEN all you have to do is go to court. He will be required to demonstrate pretty thoroughly that he a) has indeed shown interest in the child up to that time and b) ALSO can show that you, the primary parent up til that time, have such serious deficits as a person and parent that there is danger to your child.
See, the fact that a parent IS and HAS BEEN a primary caregiver to a child, has it's own 'legal standing'--your time and $$ spent on your child over time is considered valuable to the Court (as long as there is no evidence of abuse/neglect). Conversely, biodad's LACK of involvement ALSO is considered a form of standing, has it's own value in a judge's determination of such matters. The courts do want to allow both parents to have their 'parental rights' met--but they also consider the history of things in terms of the child's ongoing security/mental health/etc.
Not to mention that most judges are not really stupid--they can see when a parent is mainly working to avoid parental responsibility. His having more money and a bigger temper will NOT get him custody.
I know this whole thing can be extremely scary, especially with biodad having the economic advantage. However, it's mostly smoke and mirrors really. Consider this--he's p.o'ed now--but he will have to spend THOUSANDS, possibly tens of thousands, on a lawyer to pursue this through the courts. No matter what he is saying now, is he really going to do that? Also, if he does hire a lawyer, he will soon find that these matters are not resolved in a few easy weeks of time. They can be dragged out for YEARS--and the Courts don't care as long as it is obvious that your child is doing ok. Meantime, he'll have to keep trying to prove he's interested in a kid he's really not interested in (because his lawyer will tell him he must, if he wants any shot at all of custody). Maybe he'll spend his precious money....is he REALLY going to spend his precious TIME on a kid he doesn't really want?
I know it seems very threatening indeed-but having BTDT, in the end it is just not the threat it seems to be. A major pain in the patootie, yes, a bummer, a pointless drama. But you don't necessarily have to engage in the drama much. You and your child also have rights, and those rights are not dependent on your income.
Just quit talking to him about money. Let Child SUpport Enforcement handle it all....and legally, not only do you NOT have to discuss it with him, you have legal protection against him trying to make you talk about it.
If it gets to him pitching legal battle--then you are going to get help, possibly even from a free foundation lawyer. And I think, even if you are only a 1/2way decent parent, that you have very very little to worry about against a man who cares little/nothing for the child, and so much about his $$. I mean, you don't have to be perfect as a person or a parent--just showing actual responsible interest in your child--no worries about that, the Courts never see perfect parents because they don't exist!
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