I know you're only supposed to write thank you cards for people who brought gifts to the reception but I wasn't sure what to do about this one...we had a family couple marry us. The two of them and their children attended the wedding afterwards. We did not receive a gift from them, and we did give the couple a gift at the rehearsal dinner along with a thank you card for marrying us. Should we send another thank you card for their role in our wedding or should we leave it alone at this point?