It really is uncanny, how much Rosie's smile resembles Mary's already, and for the first time since her death there's more sweetness than bitterness in the resemblance for him. If John is as much of a brother to him as Mycroft (more so, sometimes), then Mary was far more of a sister to him than Eurus ever could have been.

"I think I can risk it," he replies, holding out his arms for her. "Come on, then, tiny Watson. You can gum my shoulder all you like, I've got a change of clothes nearby anyway."