NTA. I’ve been in that situation except I was the kid. My biological dad was a cheater and he wasn’t a great dad either. He insisted on seeing me but my mom decided that he wasn’t good for us, especially since I already had a stepdad then. I was around 7 years old when my mom decided to cut ties with my dad. When I was about 9 or 10 years old, my mom asked if I wanted to still see my dad. I said no because I didn’t want to see anyone who treated me and my mom unfairly, even if we were related. I’m an adult now and I still don’t want to see him.

So you did the right thing. Complicated things like these have to be settled between the people who were in the original situation. If my stepdad allowed my bio dad to see me when I was a kid, I think my mom and I would’ve been confused by his intentions. And your kid’s mom should know that the dad should be present or have given his consent before intruding into the life of the kid she abandoned. That’s not fair of her.