I have 3 cousins (siblings) who still live with their parents. They are all in their early 20s. I asked them all their preferred address, and they all gave me their parents' home address. I understand the purpose for sending each adult their own invitation, but do I also need to send them their own save the date? I'm picturing five photo cards of my FI and I hanging on the same fridge and it seems a little silly. Can I just address the envelope to "mom and dad lastname, daughter son & daughter lastname" for the save the date? It's not a cost issue, more of like an "I don't want them to think I'm nuts" issue. They also live in a pretty rural area with inconsistent mail delivery and I would hate for one or two of them to get either the STD or invite a few days later than the others!