yeah, I'm familiar with the rules on HoH, but he's not my client and I wasn't involved in that discussion or decision. 

She normally claims her own kids for HoH but she had a huge jump in income this year, and since she asked I told her she wouldn't get the CTC for them. I was unaware at the time that there was another person in the picture that might try to claim HoH for them which was how this whole fiasco came about. 

Maybe I should have put 2+2 together but it was the height of tax season and it just didn't occur to me. 

Now he's already filed and I frankly don't care what they do unless he wants to pay me to amend his return -- which I don't see happening.