Sure can, just count them in the RSVP, so we have enough food for everyone. Just add them in the comment section of your RSVP.
Members of the Church believe that marriages performed in temples are “sealed,” or blessed to last for eternity. The concept that the family unit can continue beyond the grave as a conscious, loving entity, with the marriage partnership and parent-child relationships intact, is a core belief of members of The Church of Jesus Christ of Latter-day Saints.
Since the couple will already be married prior to the reception days, this is a way for all family and friends to share in the marriage celebration.