I already have 2 of my bridesmaids picked out and am on the fence about my third BM. I was in both of my FHs sisters weddings, and I am afraid that if I ask one to be in mine, the other will be offended. I'm much closer with sister 1 than I am with sister 2, and sister 1's husband is best friends with my FH (we set them up). What is the etiquette on this? Do I have to ask both?