SORRY, I LOST THE LINK i am fail
[Even though Jo would have wanted to celebrate her own birthday with a night out on the town, she knows that isn't Sam's style. At all.
Instead of a cake she whipped up a few cupcakes and found some local beer that she was pretty sure Sam liked. Actual food wise she still picked up a pizza, but topped it with all of Sam's favorites instead of the half and half they usually worked out together.
It was his birthday, after all.
She piled the cupcakes on the pizza box and headed off to the room where he waited, making sure to avoid any areas of the bunker Dean might be in. There was no need for the older Winchester to see her walking around in Sam's shirt and nothing else.]