Do I have anything to worry about? If I do get a letter would the court order be suffecient proof?

I was awarded custody of my son August 6. The order states, "to grant him any and all additional relief to which he may appear entitled".  My sons mother doesn't seem to think that applies to taxes. The order clearly states ALL relief. And she continues to ignore me. With the just shy of six months of the order and every weekend and holiday I am more then over the six months requirements. So I don't know if I will have any problems if she decides to file as well. I have already e-filed as of Jan 13th.