"Ex parte" just means he did it "one-sided" without the knowledge of the other person. You need to get a copy of that court petition and order. It is usually not done, except in extreme emergency situations. Do not let this happen. Get a lawyer in MA and he/she can file a Motion to Set Aside Order or something similar and point out that your ex lied. He did this, I am sure, to get out of paying support, and possibly to "get even" with you for moving his kids away. If you cannot get a lawyer, file it yourself. Put the case name and court number on a paper and write it in the form of a letter if you have to, to the judge. Good luck.
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