child custody change....

my boyfriend and i are going through a horrible battle that has been on going for about a year now. we have just recently realized and now have written proof that his ex lied in court to obtain more child support from him. not only did she lie...but she put it in writing. she also committed tax evasion. i am wondering how we would go about proving this and if custody might change hands. i mean..she committed 2 felonies...doesn't that show that she is an unfit mother? also the child has asthma and the mother took the child off her breathing treatments before the doctor told her to do so. we have a copy of the child's medical records and it says right in there that the mother took child off treatments before doctor's consent. isn't that putting th child's life in danger? isn't that also another reason why the child is unfit. not only that but the child's mother is a nurse. doesn't that just make matters worse? help.. i know we will need a lawyer to get all this done... that's a given but if anyone has gone through this could you please help us. also when the child turns 5 visitation is going to be re-evaluated... can we request for custody to change then also because the father's living environment will be more stable than the mother's? thanx.