I'm not thinking about the court I'm thinking about the IRS. By chance if the wording is if he is current in CS only to get the deduction. He can get this through the court system causing you to both go back x yrs and redo your returns. Not judging just stating a circumstance that could arise. I wish nothing but the best for you and your family. You should be proud of how you have taken care of the children and yourself. Medical and cs arraingments are often 2 seperate situations even in family court. As odd as that sounds.