You can file a contempt action in court. The court can hold a person in contempt of court for failing to pay a child support order even if they are in jail. The parent who is in jail must show that they cannot pay the support. An incarcerated parent may actually be able to pay the support. If the incarcerated parent claims inability to pay the child support, they will have to convince the judge. The judge will decide and can take into account other sources of child support.
Remember: An incarcerated parent (in jail) may still have income or assets that they must use to pay child support. For example, interest or dividend income from investments such as stocks or bonds, money from selling investment assets such as stocks or bonds. rental income, disability, retirement, or other similar benefits. bank accounts, retirement accounts, or other accounts which could be used to support the child, or money from selling property (real estate, a vehicle, or other valuable property)
Even if the judge decides that the other parent is not in contempt, that does not automatically mean that the child support order ends. If the judge does not actually modify the child support order, the unpaid child support will continue to add up. Unpaid child support is called "arrears." The judge can later order the other parent to pay the arrears when they are able.