"What do I... do with it?" Sherlock asked skeptically, holding the offensive object at arm's length.

"She's not an it, Sherlock, so please stop that," John called, rushing around the kitchen. "And I don't really care what you do so long as you don't hurt or maim her in the ten minutes before Mrs Hudson gets here."

As if she knew they were talking about her, the baby gurgled and smiled,m prompting Sherlock to frown at the spittle falling out of her mouth.

"What if it, sorry she," he corrected, rolling his eyes, "Cries?"

"Rock her- gently- talk to her- not about murder- show her things- no experiments. Got it?"

"No," Sherlock muttered to the infant, ignoring John entirely.

"And for god's sake Sherlock, there's no need to hold her like that."

John rushed over and repositioned the baby in Sherlock's arms so she was no longer suspended in mid air, but nestled comfortably next to his chest, still smiling at him.

"Just... don't kill her," John pleaded, standing in the doorway. And with that he rushed off down the stairs.

"John!" Sherlock called, suddenly remembering something. "What's her name?"

He could practically hear the exasperation in John's voice as he called up the stairs, "Violet, Sherlock. Her name is Violet, which I've told you more than once."

Sherlock frowned down at Violet, who seemed unfazed.

He sat down on the couch carefully. How fragile were babies? If he jostled her the wrong way would she break? It was the sort of thing he'd need to experiment on, but John had specified no experiments.

So, better he be safe than sorry.

He sat Violet up on his knee, careful to support her wobbly head, which reminded him of an experiment he'd once done with gelatin. As far as babies went, he supposed she wasn't bad looking with round cheeks, big blue eyes, a decent head of hair, and a smile that might be capable of melting even Mycroft's heart.

That opinion faded shortly when the smile faded off her face and her lips quivered.

"Oh, no no no, don't do that," he pleaded to no avail. Violet began wailing, and Sherlock resisted the urge to hold her at arm's length again.

Rock her, gently. That was what John had said.

Sherlock stood up and paced around the room, not sure what gently rocking entailed. How many laps per minute? Was there an optimal rate for bouncing?

He tried several different strategies, none of which worked.

Talk to her, not about murder. Right.

"Hello Violet. John had to leave, something of an emergency he said, and there's really only me until Mrs Hudson gets here, which is supposed to be really soon, so there's no need to cry."

It didn't help.

Show her things, no experiments. Well, what did that leave?

So he rocked her over to the window, and held her up so she could look out. He bounced her over to the fireplace and showed her the skull. He jiggled her into his bedroom and showed her the periodic table.

Nothing helped.

He bounced her back out to the living room, growing desperate.

"I don't know what to do. Why don't you come with an instruction manual?"

Spotting his last resort, he carefully sat Violet down in his chair, propped her up safely on pillows, and began to play a lullaby.

Entranced by the rhythmic motion of his bow, and the soft notes that came from his violin, Violet's wailing stopped.

That was how Mrs Hudson found them ten minutes later, Sherlock still playing to her, even as she slept.