First off; my guys siblings all have different fathers, there are 4 of them. So my sisterinlaws father is single. He's had this friend who goes EVERY where he goes. My MIL doesn't like the friend because he is very handsy with my SIL. Once at a BBQ he tried getting handsy with me but I quickly put an end to that. After talking to my MIL about how he made me very extremely uncomfortable she told me he was that way with the underage SIL. Now FIL has passed, current step dad is of course going with mom and the other is in jail/ not rights to kid situation. He knows everyone at the wedding/no drama. Is it ok to not give him a plus one?