The first time was when John came down with the flu. Sherlock had babysat his goddaughter—well, adopted daughter as of last month, he thought with a fluttering heart—on many occasions, but this was the first time he had 24/7 responsibility for her. He would have to do everything, from feeding to changing to bedtime and bath time. The latter was what ended up being the problem.

Up to this point it had been going well. Rosie had been fed, changed—constantly, Sherlock thought—and generally kept safe for the past two days. But now the peas that she had spilled all over herself at dinner were sticking to her skin, and there was no getting around it. He had to bathe her.

A simple task, Sherlock thought, and at first it was. Rosie loved baths, so there was no fuss other than her excessively splashing the water and soaking Sherlock's clothes. He didn't mind that; seeing her smile up at him and babble from her little bath in the kitchen sink more than made up for it. But as he took the soap and scrubbed her arms and legs and back and got her hair all sudsy, a thought occurred to him.

Was he supposed to wash her…down there?

He paused mid-scrub and thought. It seemed like he should. It could get dirty just like any other part of the body. John had told him in no uncertain terms that he was to make sure he wiped every last nook and cranny when changing her nappy to ensure there was no mess hiding. But would it be appropriate in the bathtub? It was one thing to use a small baby wipe to quickly clean up a mess. Pushing a big bar of soap between her legs seemed more invasive. And if he did, he'd have to wash it out. That could involve even sticking his fingers in there. Just the thought made him nauseous. What if he hurt her?

"Um…" he murmured to himself, stopping his scrubbing while Rosie continued to splash, blissfully unaware of his predicament. What if it was invasive and he traumatized her without meaning to? What if he accidentally broke her hymen? What if she ended up needing therapy later on in life because of Sherlock and John found out and decided to divorce him and leave and…shut up, he scolded himself.

Still. Despite his extensive study of human anatomy, Sherlock knew nothing about vaginas. If he didn't wash Rosie's, could it get infected? He had read that they were self-cleaning, but how much could they clean on their own? Maybe he should look it up…

"Sherlock?" Mrs. Hudson called. Rosie squealed at her voice and splashed again, sending a wave of droplets over Sherlock's shirt. "Need any help?"

"I—yes," he admitted, thinking it best to be truthful. This was for Rosie's safety, after all.

Mrs. Hudson came in quickly and beamed at Rosie's smile and the massive stack of bubbles on her head. "So sweet," she cooed. "How's everything going?"

"Fine. I've washed everything but the," he nodded.

Mrs. Hudson looked confused. "But the what?"

"You know."

She shook her head. "I really don't."

"Her…little girl part." It was the best child-friendly euphemism he could come up with.

Mrs. Hudson laughed. "Oh Sherlock, are you afraid to do that? Here, it's easy. Let me show you."

Sherlock wasn't sure how Mrs. Hudson could know how to bathe a baby since she'd never had one, but he wasn't surprised that she did. "You just take a dab of the baby soap," she showed him. "Here, hold her still for me. Thank you, now just watch as I go front to back, like this. Just like you do when you're changing her."

Rosie kept giggling and making baby talk, and Sherlock relaxed. She didn't seem to be traumatized, but then maybe that was because Mrs. Hudson was doing it. Possibly reading his mind, she handed him the soap and said, "Now you try."

Sherlock took the shrinking bar and tried to do exactly as Mrs. Hudson had, as gently and lightly as possible. "That doesn't hurt, right?" he asked anxiously.

"Ba!" was Rosie's answer, kicking the water. Mrs. Hudson laughed.

"Now how do I wash it out?"

"The same way you would wash any other part," Mrs. Hudson said in a teasing tone, and Sherlock scowled a bit. Of course. It was perfectly simple. Or at least it was until he had taken the loofah in his fingers and actually had to use it.

Rosie was looking up at him with adoring eyes, and for once she was staying perfectly still as Sherlock moved his hand between her legs. He stopped.

"What's wrong?" Mrs. Hudson asked, her smile fading.

He handed her the loofah. "Watson would be probably better if you washed her."

"Oh Sherlock," Mrs. Hudson squeezed his damp shoulder. "You're doing fine. Really."

Sherlock didn't move. The water was rippling and reflecting the light in a way that reminded him of the pool. He shut his eyes to avoid the onslaught of those memories. As much as he loved every minute with John, it felt like their friendship had been riddled with good intentions turning into mistakes. Going to the pool alone had resulted in John getting kidnapped. Faking his death had resulted in John grieving and distrusting him. Wanting to surprise him at the restaurant had resulted in John being angry. What if this was another case where he wanted to help but would only make everything worse?

"I can't risk hurting her," he said. "I couldn't do that to her and John again."

"Don't worry, you won't." Sherlock turned and Rosie squealed, "Da-dee!" John's face was still pale with red-rimmed eyes, but he was smiling. His voice was fifteen percent clearer and less scratchy than it had been before too.

Mrs. Hudson stood up. "Oh, John, it's so nice to see you looking better. I knew that chicken soup would help."

"It did, thank you," John nodded, and Mrs. Hudson left, as their small kitchen was quickly getting crowded. John stood beside Sherlock and took his arm. "I've washed my hands, but you may want to scrub up afterwards just in case."

Typical doctor. As if Sherlock cared if he caught John's flu. "You sure you're up to this?"

"Course I am," John said a tad impatiently. He guided Sherlock's hand and helped him to gently rinse between Rosie's legs. "Just like that, nice and gentle." Sherlock smiled at the warmth of John's fingers and his careful movements that were laced with love. He was just starting to feel relieved when he noticed Rosie had stopped smiling. "Eh," she said a little angrily as her eyes began to droop.

Sherlock froze. "What's wrong? What happened? Why is she acting like that?"

John snorted. "Because she's tired, you git. You've kept her in the bath past her bedtime."

"Sorry," Sherlock said, and immediately plunged a hand into the water to drain the tub. It groaned and began spiraling down like a little tornado. He should have been keeping track of the time; how on earth did he not think of that? Now Rosie's whole sleep schedule would be thrown off.

"It's all right," John said more softly, reading his mind. "Just dry her off and put her to bed. I need to be getting back to bed myself."

Sherlock quickly poured the bucket of water over Rosie one last time before it was all gone, and then lifted her out. She was significantly less vocal than she had been when he'd picked her up to put her in, and now she rested her head on his shoulder. He found his arms cradling her tighter almost involuntarily. For the first time he felt a wave of sentiment similar to what he'd always felt for John, and kissed the side of her head.

She had fallen asleep by the time he had gotten upstairs to the nursery to dress her and put her in her crib. Sherlock leaned with his elbows on the rail and smiled.

He was only a month into parenthood, but he already loved his new daughter as fiercely as her father.