Child support payments usually stop at age 18, unless some payments have been missed along the way ...
Providing ALL your payments for child support are fully up to date and paid in full, you can file in court to have these stopped.
How do I stop the payments now?
Start by making an official notification, in person, to child support enforcement. Take names of you you talk to. Get a printout to make sure you show as current on your payments.
Child support payments change or stop only by order of the venue that issued the order for support.
Show the court that: the child is deceased; the child has been adopted; the child is emancipated; the child has attained majority; and/or you have no income other than public assistance; and, you do not owe any past-due support.
You can stop child support payments on the grounds that the child is not your biological child only if you did not know that when you agreed to the support, and if a Court approves your request to stop.
You send in your child support payments regularly and on time.
Keep current on your child support payments and make sure the courts are recording payments correctly.
If you relinquish your parental rights, you are still not going to get child support payments. The child support is for the child.
In most cases, a mother cannot legally stop child support payments without a court order. Child support is typically mandated by a court and must be paid until the court modifies or terminates the order.
Your spouse has no authority to over-ride a court ordered child support.
Whatever you do, do not stop paying child support. You have to get the current order modified by a judge to be able to stop the payments.
Generally, yes, the child is still his child. The support payments would likely stop if the new husband adopts the child, but he can't do that unless you agree to it.