
Oh, thanks, it's Sally
from Nightmare Before Christmas.
The Big Bang Theory Season 8, Episode 8

You know how Sheldon is
if he sees Christmas stuff
The Big Bang Theory Season 10, Episode 12

Gather around, kids. It's time for Sheldon's
beloved Christmas special.
The Big Bang Theory Season 2, Episode 11

To be fair, we may have been on edge
because of the Christmas tree.
The Big Bang Theory Season 10, Episode 12

the broken Christmas tree
lights, so it was after that.
The Big Bang Theory Season 12, Episode 18