A/N: I've been having a SERIOUS McStizzie withdrawal lately. Just so you know, there will be more.

Just to let you all know, since I have to have everything I post here labeled, I created the GU for myself. Which means GA AU. In other words, this would be happening in my GA world/fic, but it's not happening on the show.

I hope you get that, if not, sorry. Hope you enjoy it!

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Walking through his penthouse and into his living room, he had stopped. He blinked and took a double take.

"Hey." His girlfriend smiled as she walked out of his kitchen. She had obviously gotten here earlier, and he fare well knew it.

"What did you do to my living room?" Mark asked glancing over the room.

"I put some things up to celebrate Christmas, which is in three days by the way." She told him, as if he didn't have any idea when the holiday was.

"I can see that." Mark observed.

The room had Christmas lights going around the room, a wreath, which also had small green and red lit lights, and two stockings hung behind the wall of the couch. Which he guessed was because he didn't have a fire place. A cheerful, round, holiday rug lay under the coffee table. A Santa statue was atop the coffee table.

"You need a tree though." Izzie said thinking that it needed just that for the holiday feeling to be in full effect.

"I need a tree?" Mark asked her with a raised eyebrow.

Izzie walked towards him. "Yes. It's almost Christmas and you don't have one yet."

Mark glanced at her. "It's like Christmas threw up in here." He commented.

Izzie rolled her eyes. "Why have you been so reluctant about the holiday? It hasn't even been today, so no making an excuse about it being me Christmas-ing your place." She told him, putting her hands on her hips.

Sighing, Mark knew he would be fighting a losing battle if he refused, so instead, he took her hand and brought her to his couch and sat her next to him.

Izzie looked at him as he leaned back against the couch with a sigh, and a moment later, he looked at her.

"The last real Christmas experience I had was with Derek, Addison, and the Shepard's, who you know are like family to me. Thinking that I wouldn't be spending it with them, my family… I haven't been in a big Christmas mood." Mark confined in her.

Izzie put a hand to his cheek, and gave him a small smile. "I could be your family."

Mark studied her a bit before putting a hand on her waist and kissing her. Then he gently pulled her to him in a hug.

A few moments later, they pulled away just enough to look at each other. "Thank you for telling me." Izzie said softly.

"Thank you for being my family." Mark said just as softly.

Him saying that gave her a burst of warmth inside of her. Not wanting to ruin the moment between them, she rested her head on his shoulder.

Not one to feeling even a bit vulnerable, Mark spoke. "What have you been baking this time?" He asked, smelling the sweet aroma coming from the kitchen.

A smile spread across Izzie's face. "Sugar cookies. I also made them in shapes of trees." She added in.

Looking at how excited she got over the smallest things, it made him feel a lot better.

"Oh!" She stood up, detaching herself from him. "I need to take them out."

Mark watched him with a smile as she ran to the kitchen.

She was his family.