Sherlock tried not to let the disappointment show on his face.

He almost succeeded.

"Goodnight, John."

Sherlock turned away and headed towards the window. He picked up his violin case and took out the instrument. Still not facing John, he took a moment to tune it before he started playing. It was a slow tune, not mournful, but soft and slightly melancholy, a song that he hoped would help soothe his friend to sleep.