If your finances have changed since the original court-ordered child support was issued, you should contact an attorney immediately to petition the court for a reduced amount of child support. Not until you do this will your monthly payments change.

This means that every week will count. So, you need to do this ASAP.

It doesn't matter that you are on SSI or expecting disability. It doesn't matter that you are unemployed. If this is not documented in court, you will be financially responsible for the child support that is currently in effect, and you will be going into arrears. Usually, this situation will not be retro-activated, which is why, again, it is important that you seek legal representation and attempt to lower the child support payments.

Each state has a different penalty for non-payment of child support. Some states will even suspend driving privileges.

Find yourself an attorney.

Filling out an application for social security won't stop any legal proceedings against you. If that were true, every parent that has not paid support for any reason would simply trot on down to the SS office and claim they are exempt from prosecution for non-support by applying. By the way, you can't collect social security when you're an inmate, as the state will be already providing you with all you need during your stay.