Well, I've done all I can with the birthday post card project. The whole thing now hinges on family participation.
I mailed thirteen packets out with post cards and instructions to Carey's siblings, their spouses, and their children / families. My mother-in-law will (hopefully) receive 21 birthday greetings from it.
Should I get to count any of this
I think I will count five...because I added handwritten notes to four of the instruction packets' form letters, and the post card that I mail to mom-in-law will have a handwritten note on it as well.
Keep your fingers crossed for me that everyone participates, and that the post office gets them delivered damage free and on time.