You didn't realize how fast the time flew by. You forgot yourself, bogged down in your duties. It wasn't until Hackett gave you the order to rest that you looked at the date. It's Christmas. Once inside your apartment on the Citadel, you felt a sudden emptiness

"Please tell me we really need this thing and the Joker wasn't messing with me" It was Garrus. On your doorstep. And the Christmas tree in his hands. He was trying so hard to cheer you up "This thing is so prickly, Spirits.."