A few of my grandparents siblings are alive, four of which I was closer to as a child and are healthy enough to reasonably attend my wedding. The problem is that my wedding is 1 to 1 1/2 hours away. All four are over 85, and all still drive, however I would feel uncomfortable with them driving to my wedding. There would be no other invited guests they could drive with, as none of their children or grandchildren are invited and my one aunt/uncle will be flying in and staying at our hotel block. I was planning on giving the three singles and even the one couple a +1 for drivers... How rude would it be to tell them their +1 is for this purpose? Maybe the three singles would pick up on it, but what about the elderly couple? It would be odd to send an invite to Mr and Mrs plus guest.