Ok, my ex-girlfriend and I had 2 sons, she got custody of one and me the other. So, there was an order for no support be paid, even when she filed for assistance and tried to amen it. Can I collect child support from her now, from the time she sent the son she had away to an assisted living facility, and I still raised my other son with no help from her?

If you file for temporary modification you may have some success.