There is a case that clarifies the Mother's duties in this situation. You will want to clearly, effectively and persuasively tell the facts and story so as to fit into the legal principals expressed in the case. Unless you have the skills and experience to do this, an attorney is your best bet. I don't know what you mean by "huge amounts of money"but a couple thousand would be a reasonable expectation.
Sign up to receive a 5-part series of useful information and advice about child custody law.