I'm in a predicament. My little sister is one of my bridesmaids and I am taking a chance even having her in my wedding because she is a mess. Not sure if she's on drugs or what but I have given her the option to opt out of the wedding but she really wants in. That being said if she comes to the wedding her boyfriend is a disaster and she thinks he's invited. My fiance and I have decided he is not welcome after his rude and wasted behavior at thanksgiving. Do I just tell my sister straight up? We already are paying for her to go to our destination wedding but I REALLY feel strongly about him not going. What is proper etiquette?