Do I have to ask my fiance’s sister to be a bridesmaid?

No, you don’t. But even though you’re ultimately not obligated to include her as one of your bridesmaids, it would be a welcome gesture and may avoid hurt feelings. Keep in mind that your future sister-in-law is about to become part of your family. Perhaps you’re thinking of not asking her because you don’t know her well. But inviting her to be your bridesmaid would probably strengthen your relationship. As you think it over, why not ask your fiance for his input? He might have insights you haven’t even considered. Ultimately, your decision will crystallize.

Peggy Post, our Etiquette Expert and internationally known spokesperson for the Emily Post Institute, answers your questions and provides helpful etiquette advice on everything from attire and invitations, to toasting and receptions.