As an attorney, I only do adoptions, so this is not really my area, ... but your question is really more practical than legal: Suppose you ALREADY HAD a judgment against this guy for all that back child support. If he's paid NOTHING for 17 years, and is now in jail, how likely is it you're going to get all that money? Or even much of ANY of it? Not very. Also, a judge evaluating an action seeking it MIGHT (not bound to, but MIGHT) find it curious that you waited 17 years before hauling the guy into court to seek child support. It depends on all the circumstances, of course (like, if he's independently wealthy?!), but it would probably be throwing good money after bad.
Child support is not set retroactively. Assuming you did what a prudent mother would have done and filed for child support right after he was born, and you never received what was awarded, THAT you can try to collect. If you waited until now, you cannot rectify that huge mistake, and can only seek child support for a brief future time.
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Georgia does not award back child support where there was no court order, so you could file now if you wanted to, but it would only be in effect until your son turned 18. Hard to imagine it would be worth the time and emotional distress.
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