If your mother had a child support order that went uncollected, she could certainly try and collect back owed child support if the state of Alabama allows. And I believe that it does. It would be retroactive to the date of the order but there my be a cap in your state. You, unfortunately, can not collect it as the child.
Alabama does have a statute of Limitations to enforce a child support order. It is 20 years from date of judgment for purpose of obtaining an order of support. You should have your Mother check with an attorney.
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