I'm sure this question has been addressed here on TK, but I couldn't find it on this board. We are starting to receive gifts in the mail. I know that thank you cards are not sent until after the wedding, but is it appropriate or inappropriate to say thank you to a friend or coworker whom you see every day (even if you haven't opened the gift yet)? It seems odd not to mention to someone that you received a gift from him/her, but perhaps it's proper NOT to say anything until the formal "thank you."