I have a problem that I haven't been able to resolve.  One of my clients married in June, 2019. Her Mother, thinking they supported Karen half the year, claimed her on their return, and filed Karen's return as a dependent being on her parents' return. (we didn't know this) So I filed MFJ.  Of course, the IRS caught this right away and we got a refusal on the e-file.  Mike will owe $$ if I file him by himself, so that won't work.  I explained to the Mother that both returns needed to be corrected. The parents' return without Karen as dependent, then file Karen as Single, not dependent.  The  Mother did this  So, now, do I file a 1040X?  Mike hasn't filed yet, but I do have to file an Amended because of Karen's position - don't I?  When I e-file the 1040X later this month, I will (hopefully) be able to explain this mess. Please give me some input on this, if you would.  I keep second guessing myself.