You are partially wrong and partially right. SSI (and possibly disability, depending upon the type) have additional funds built in for child support. Your ex is responsible for that amount. The fact that your letters were delivered and possibly not given to your ex may or may not have any bearing. If the letter was from you and not any sort of court notice, then it would not have been sufficient to secure child support in any event. If the "letter" was notice of a court proceeding it was good service and you should have followed up on it.
You should have acted a long time ago, but better late than never. Your best course of action is to retain private counsel as this would be the quickest and best way to a resolution, plus you could get any other unresolved issues taken care of. If you cannot afford a lawyer, you can seek the services of a legal aid office if you qualify. You might also be able to contact the state's attorney's office child support enforcement division. Keep in mind that this will be very slow and tedious due to their caseload, and they only handle child support.
The sooner you start, the sooner things will be over for you. You have always been entitled to child support but you were not proactive enough.
I do not understand------? Didn't your divorce papers specify child support payments? If he was working at the time they should have and a support order shoud have been entered. That amount set in 2009is still the amount owed by him unless he went back to court to have it lowered or stopped. If he is on SSI or disability he still owes child support. Go in for a consultation with a lawyer who has expertise in collecting child support.
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