You are the sister of John Watson, that's how you end up so many times at baker street, you are a police officer as a result you're very efficient for Sherlock and Mycroft, Mycroft knows that you keep an eye on his little brother and Sherlock has all the informations he wants from you.

At christmas, John knows that you are alone tonight so he invites you to spend the evening at baker street with him, Sherlock and a few other people like Molly, Greg, ms. Hudson or Mycroft. John saw that Mycroft is not unaffected by your presence and your smiles, that's why he asks him to come.

As Mycroft enters, he saw you talking with Molly on the couch in front of the fireplace. He smiles a little bit, not even Sherlock can see it, he's secretly pleased that you're here tonight.

He steps closer and stand in front of you and Molly.

"Mind if I steal you for a little bit?"

He asks as he looks at you.