The Insanity Continues

I know I don't post here much (at all) anymore, but this isn't something I'm comfortable ranting about on TikTok for reasons I will explain under the cut.
( So you can skip if you want )

So, my ex came by to check on Vic. Everything was going fine until Vic asked about her half-brothers. He said one was playing/sleeping and the other was playing. She asked which was which and he said, "Christopher was on the floor playing with your mom." I went o_O and asked, "Did you just call April her mother?" He nodded and said, "I did." I told him, "How dare you come into my house and call another woman my daughter's mother!?" He tired to say it was the first time but I know it wasn't. There's no way it would have fallen from his lips that easily if it was. Not to mention there was a time when Vic would get punished if she didn't call April 'Mom'. It would be different if I wasn't around but I am, and I have full custody. Rob only has visitation rights.