Sherlock sends a Christmas box

[jaclyn_ellison]

So I'm trying to find the fic that begins soon after his grandfather's funeral (I think), and somehow Sherlock ends up sending a box for a soldier. John is the recipient, and is amused and intrigued by the message on the card, finds a forgotten receipt with Sherlock's name and address, starts up a correspondence, and.... can't remember any details after that. I just have to read Sherlock's card again; it was so very Sherlockian!
Thanks for any help.