If you don't stand up and say something, nobody will. Don't see it as being rude or anything like that. You're his mother and you have the right to tell people how you feel when it comes to him. Be strong mama, protect your baby.

I'd tell them straight up, please stop kissing my son. I don't like it. I don't make it a habit to kiss other people's kids so I wouldn't want anyone thinking it's okay.