Mil issue

So I was told to start my own thread cause you guys can help. I'll try not to make it long and if you want more BG then I'll comment it. BG- we put my mil on a TO right before we found out we were pregnant with lo, because when we would go over there they would never speak to me, only ask stuff about my family for gossip(they hate my family, and they hate me honestly) They kept trying to break us up, example. Dh told them he was going to ask me to marry him and they said no that we should break up and see other people and if we were meant to be we would come back to one another. I have a lot more reason why we put them on a TO(if you want them I'll tell them). When lo was a month old, I started to feel guilty and decided to let mil meet him for the first time. That opened up a flood cause I guess she thought we were letting her back in and she started showing up at the community building track where we would walk on afternoons just so she could see him. Then started asking us to come over and we did cause my dh other brother had not met lo yet and he was there with his wife. We put them in another TO after Christmas and lifted it not too long ago.

Anywho, my mil sometimes kisses my lo on the lips, when she gets him she always turns him at a angle I cannot see where she kisses him. I asked my dh to take care of it but he says he doesn't see her kiss him on the lips (not paying attention like I do, I will admit I hover, never leave him alone with them(sfil and mil). I want to try to take care of this before baby #2 is here (21 weeks pregnant) would it be ok to text her telling her that we don't want her to kiss him on the lips or should I do it face to face?