A/N: Hello, people!

I don't own Sherlock.

I have no beta.

ENJOY!

Sherlock gazed down at the little girl currently clinging to his trousers. Wispy, strawberry blonde hair, curled in random directions, framing a rounded face that was a sign of baby fat that still lingered. Deep blue eyes blinked up at him in happiness.

Sherleen Penelope Watson, his goddaughter.

"Sherry, are we going to do an experiment now?" she asked, lower lip protruding slightly, eyes bulging.

Sherlock felt his heart skip a beat, before he regained himself and nodded.

"Yay!"

She jumped back and threw her hands up in the air. "It's like Christmas!"

The little girl scrambled to the closet, where she kept her very own labcoat(courtesy of Sherlock) and slipped it on. She grabbed her rubber gloves and her protective lenses, before returning to the kitchen, prepared for whatever Sherlock wanted them both to undertake.

"I'm ready!"

Sherlock stared for a solid minute, filing away her appearance for his special Sherleen Room, in his mind palace. The image was saved under the date and placed inside the rotating closet of memories he had of them experimenting together.

He snapped back to reality and smiled down at the little human that John and Mary created.

"Do you wish to hear of the experiment?"

She nodded excitedly, eyes, so much like John's own, widening.

"We are going to observe various Planaria in the slides. Once they've been properly labeled, we'll be testing their reaction to hydrogen cyanide. I will be handling the cyanide. Make sure you keep your gloves on at all times."

She nodded, a serious expression coming over her face.

Sherlock nodded in return, glad that she was able to follow simple instructions. "Now, do you know what Planarians are?"

"You said they were flatworms," Sherleen stated, giving him a measuring look. In truth, he had explained it to her. About a month ago. He was impressed that she remembered what he had said. Her current look must come from the fact that she was daring him to answer in a negative and therefore proving himself to be a liar. Sherleen did not like liars. She had a remarkable knack for deducing liars, much like Sherlock could.

"I did. Well done."

She grinned in triumph and skipped over to the refrigerator, where she pulled a booklet from the counter beside it and placed a sticker on the large board taking up most of the freezer door's space. It was for when she answered questions correctly. Every twentieth sticker earned her a surprise.

"Now, we shall begin."

All throughout their experiment, he quietly asked the small eight year old, questions regarding their work. He kept a mental tally of how many more stickers she earned.

After an hour of hard work, they'd finished, Sherlock internally marveling over how intelligent she was.

Sure, he begrudgingly had to admit that Mycroft along with himself, were both unnaturally intelligent at her age, but that was a rarity among people in this current day and age. Sherleen would be a genius, Sherlock would make damn sure of it.

They added the stickers to the chart and she turned to him expectantly, grinning. "That's another twenty!"

Sherlock nodded, holding up a hand as a signal for her to wait. He disappeared into his room and reappeared a moment later, carrying a box with three numbers on it.

1.

2.

3.

"Pick a number," he said.

Sher studied the box. It was a plain brown color. Nothing other than the numbers that could give away what was inside.

"Two, please?"

Sherlock nodded and reached inside, procuring a rather large object with a blue bow on it. Sherleen loved the color clue after all. He remembered that specifically. John liked blue too.

The little girl squealed and jumped up and down, like any excited child was wont to do.

"Thank you Sherry!"

Sherlock handed the gift over, fondly recalling when he received his own high powered microscope. Of course Sherleen's was a MW4-H3 Binocular Microscope, a much better version than what he had gotten at her age. Still, the moment and reaction were very nearly identical.

She cradled the expensive piece of technology in her arms and smiled brightly. "Thanks again!"

Sherlock smiled a little and handed over a small box of glass slides. "For you to start your own experimenting. Safely, mind you."

"Yes, sir!"

Sherlock watched as she moved off into the living area in order to properly situate her new belongings. He made sure to file the day away in his mind palace. It was important of course. Just like all other days with Sherleen and John were.

A few hours later, the little human was ready to depart from Baker Street. John and Mary were sitting on the sofa, listening as she regaled to them, her adventures that evening. She proudly displayed her newly acquired gift for them to see, warning John about touching it, since she knew very well that he was clumsy.

Sherlock smiled as random memories of John's failing equilibrium, flashed through his mind in a quick slideshow of images.

John huffed but nodded. He looked up, catching Sherlock's gaze.

They stared at one another. Those glances. They used to happen so often. How John's blue orbs would trail down slightly and then back up.

Sherlock's heart probably just stuttered. That, or he stopped breathing.

John blinked and the moment was gone. He returned his attention to his jabbering daughter, leaving Sherlock to stare into nothingness.

Right before they departed, Sherleen threw her entire body weight at Sherlock, giggling when he caught her easily.

The little girl wrapped her small arms around his neck and pecked his cheek. "I love you, Sherry!"

Sherlock offered a grin. The one he used to give only to John. The one he now also shared with his goddaughter.

"The sentiment is returned wholly."

She winked and he placed her back on her feet.

Mary hugged him quickly, patting his cheek lightly.

John mimicked the action and Sherlock instinctively wrapped his arms around his best friend. He wanted to hold on longer than what was deemed, 'appropriate' but knew that John would raise question about it.

They parted and John murmured a low, "Thank you."

"Not a problem."

Sherlock waited for the little family to disappear down the stairs, before moving to the window to watch as they walked down the pavement. Sherleen in the center, hands being held on either side by her parents.

His throat constricted. Emotion. Sentiment. Chemicals calling for bodily reaction.

He sighed and turned around, annoyed with himself.

If only he'd thought of a better plan all those years ago. Ten years to be exact. If he'd not 'killed himself', Sherleen would be his daughter and John would be his husband.

But such was not meant to be, obviously.

A/N: Done! Sherleen's microscope is worth like, $700. About £450.

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