My children moved in full time with me back in March of 2011. In February 2012 my ex-wife finally signed a new custody agreement stating I am the primary custodial parent. When I ask her for any financial assistance she instantly says she wants the kids back half of the time and is never going to give me a penny. If I don't ask for help, she doesn't want the kids back. I am trying to last as long as I can without any money from their mother. My question is, once I do file for child support will they require her to pay back owed support? Would it be from the date they moved in physically? Or from the date she signed the new custody agreement? Thank you in advance for your help. You are a good human to help out of the kindness of your heart!