What is the name of your state? arkansas: i need to know if i can sue my ex for back child support. ok here is the story both my boys lived with me i am their mother, up intill they both turn 17 at different times though. one son is 23 and the other is 18 now. my ex owed back child support from the start, but when my first son moved in with him my ex started paying some what better for my youngest son. i would say he is about $8000.00 in the hole, but my ex does not think he owes me anything and i am wondering if he does? he thinks that sense he had one son for a year and i had the other child and he paid me a few payments that we are even and he owes nothing and i have doctor bills he has not paid his part on either. i hope i explaned this and made some since. can you help me ? thank you.