XP has DD on Sundays, but his plan for today was to drive her long distance to a family bbq. I was worried, as I know he'll have a drink and think it's ok (he drinks when they're local but at least then he gets taxis). Then he told me the house they're going to has a pool. I have concerns about how well he supervises DD when he has her anyway, but the pool factor just hit me in that instinctive, mother, gut reaction way. DD has been a little under the weather, but nothing that would normally make me say she can't go with him. But I did exaggerate how she was in order to stop him having her today. He didn't believe me, of course, said he was coming round to see her himself, but I made excuses (she'd been up all night, was now sleeping). I've never stopped him seeing her before, and I do feel bad for both him and her, but I just couldn't let her go with him, knowing what he's like, and having the fears about today that I had. I just couldn't face having another argument with him about his drinking, had I told him my concerns. BTW, DD and I had a fantastic day today, she's too young to know today is 'daddy's' day. So AIBU when my gut reaction is 'no'?