A/N: A short little ParentLock! drabble that refused to leave me alone to study for finals until I got it down on paper. This features an undefined-female/Sherlock pairing. I have an OC in mind, but she may or may not ever make it to print so for now, it's up for your interpretation. I'm not entirely pleased with how the ending came out, but I think it's fun to imagine anyway. Anyway, be nice if you review and have a lovely holiday.

"Bored!"

Sherlock looked up at his daughter's voice, moving his newspaper so the young girl could clamber up on his lap.

"Mummy and me were gonna paint nails today but then she hadda go work."

"Mummy and I," he corrected gently, laying the paper aside to situate her more securely on his lap.

Olivia rolled her eyes in exactly the same fashion as he was known to. He smirked at the five year old, eyes widening when she brought both hands up to grasp his cheeks, pulling his head towards her.

"Papa, you're not listening! Mummy was gonna put sparklies on my nails and then let me paint on hers. Will you do nails with me, please Papa?"

Sherlock scowled. He was a consulting detective, not a manicurist. He did murder, not nails. (He did, however, do tea parties, because there was nothing wrong with drinking tea even if he did have to sit at Olivia's pink plastic table with a tiara on his head.) His daughter slid off his lap and tottered into her bedroom, pulling the bottles of nail polish in question from her vanity. She thrust them at him before climbing onto a chair at the dining table, waiting for him to join her. Sherlock sighed, turning the little glass bottles over in his hands. One was multicolored glitter, presumably the 'sparklies' Olivia had referenced and the other was a soft peach color he recalled his wife favoring.

"Papa!"

The shrill call cut through the air again and he turned to his daughter who was pouting up at him through a tangle of dark curls, tapping her fingers on the table. Flicking his eyes skyward with another sigh, Sherlock joined her at the table and began carefully applying the glittery polish to each of her small fingernails, smiling fondly as she zealously blew on one hand as he painted the other.

"Now your turn!" Olivia stated triumphantly after her nails were fully dry.

Sherlock didn't even try to stop her as she pulled his hand forward and started to messily paint his nails with the peach polish, poking her tongue between her lips in concentration. Just as she was about to move to the second hand, a knock sounded at the door. Sherlock got up to answer it, absently shaking his painted hand around to make it dry faster as he'd seen his wife and daughter do.

"Cross-dressing again I see," Mycroft drawled, eyeing his brother's fingernails as he pulled open the door. "Business or pleasure this time?"

"Oh stuff it, My-" Sherlock was interrupted by a small voice.

"Uncle Myc!"

Olivia excitedly hopped down and rushed her uncle with a hug around his knees. Mycroft affectionately ruffled the girl's hair, stooping down to give her a proper hug in greeting.

"Livi, wouldn't Uncle Mycroft look lovely with some sparklies?" Sherlock asked slyly, knowing his brother could never deny Olivia anything.

The young girl's eyes lit up, ignoring her uncle's horrified expression. She tugged the older man by the hand to the table, handing her father the bottle of glitter polish to open for her.

"Papa, I have to do Uncle Myc's nails first, he's very busy. You understand," she stated seriously, pushing the open peach colored polish towards him.

"Of course, Livi." Sherlock chuckled, "You can always finish mine later."

"Olivia, maybe I shouldn't get any sparkles," Mycroft tried, attempting to wriggle his hand away.

"Uncle Myc, your job is to fix problems. Sparklies make people happy. Happy people don't cause problems." Olivia explained patiently, patting his hand.

Sherlock bit his fist to keep his mirth under control. Mycroft was so taken aback, he fired off a quick text to Anthea before surrendering his hand and settling in to let his niece do her bidding.

Will be a while longer than expected. Please have acetone waiting when I return.

"So Mycroft, other than the manicure, why did you stop by?" Sherlock grinned, taking a seat across the table.

"I have a case for you to look over, and I've brought some old files for you to use to help Olivia with her deductions." Mycroft replied, sliding a thick pile of folders towards his brother.

"Uncle Myc brought stories to play the game with?" Olivia asked excitedly, "Thank you!"

"You're quite welcome, Olivia." Mycroft replied, eyes softening as he looked down at his niece who was just finishing applying his 'sparklies'.

"There, now blow on them or you'll smudge!" she chided, pulling her father's unpainted hand towards her to finish. "You too, Papa!"

The Holmes brothers looked at each other, sighed, and dutifully obeyed the young child, helpless to resist. Later, when Olivia's mother returned, the world's only consulting detective and the British government himself greeted her; with painted fingernails and a tiara each, drinking tea at a pink plastic table.