@jjilyeah: I don’t have anyone else on whose behalf I send greetings, but my niece Penelope always writes something along the lines of “Dionysius, Sophia and Arianna join me in wishing you a Merry Christmas; love, Penelope”
The principle is that an ethical adult does not sign other people’s names to documents, even social documents like a Christmas card. Rather, one would include the other people by mentioning them in the body of the letter. It is a great principal to start practicing now, as it applies to thank-you notes as well, wherein you might write “Husband-Darling joins me in thanking you for the lovely epergne, which will come in so useful. Love, Jjilyeah”
Speaking of Christmas cards, which I am so glad you have introduced on the board, now is the time for all Bees who think they might ever need to send out invitations; whether waiting, or planning now, or planning to plan someday; to take advantage of the Christmas Card custom. Those cards arriving at your home, your parent’s homes, and your future in-laws’ homes have return addresses on the envelopes!
Collect the envelopes, and start putting together your mailing list from the return addresses! The best way is to create a “visiting book”. Get a lined journal that will lay flat, and write one family per page. Start with the social name of the heads-of-house with their titles, if you happen to be lucky enough to have received a return-address sticker that includes names and titles. Under that, list their first names one to a line, and then the names of their children. If they might be adding more children, then skip a few lines so they can be added to your book, and write “received card Christmas 2012”. At the very bottom of the page, write in the address. Over the coming years, when you invite them to dinner or go to dinner at their house, send a card, receive a gift, and so on, write it on this page. It will be an invaluable reference to help you avoid giving the same Christmas gift two years in a row, or being the one who always eats out on them without ever returning the invitation, and so on. When they move, you cross out the address and write in the new one on the line above from their change-of-address card (assuming they send one). And when you go to start addressing invitations, you have all the addresses there at hand.