My mom is getting married December 2010 and my fiance and I are getting married May 2011. My mom is definitely going to invite my fiance's parents to her wedding in December. However, we are not sure if we should also include my fiance's brother, sister, and sister's fiance. Is there a correct or polite thing to do? My mom obviously has a relationship with my fiance's parents because of our upcoming wedding, and she has been around my fiance's brother and sister a handful of times. If my fiance's sister is invited her fiance also must invited, but my mom has only been around him maybe once or twice.
Basically, my fiance's parents are being invited to my mom's wedding because we think that is the polite and right thing to do. We definitely dont want to hurt anyone's feelings and make things awkward for my wedding in May 2011... What is the best thing to do about the rest of his family?