Disclaimer: Co-authored by the brilliant Neverland8. Neither of us own BBC Sherlock or the Artemis Fowl series. Neither of us created this headcanon. And, last but not least, neither of us owns The Hobbit.

A/N: Well all you need to understand for this story is the headcanon, submitted by an anon to the BBC Sherlock Headcanons blog on tumblr, which states that Angeline Fowl, Artemis's mum, is Sherlock and Mycroft's sister. KUDOS TO YOU, ANON, OUR HERO.

Also the ages are as follows: Mycroft is about sixteen, Sherlock is about eight, Angeline is about four or five.

Enjoy!

Flies and Spiders

"If you don't open the door, I'll pick the lock and barge in!"

Sherlock was surprised when his elder brother, reportedly up to his eyes in schoolwork, complied. A smug grin spread over the little boy's face, but suddenly disappeared as Mycroft began to block the door with strips of silver duct tape.

"That's not fair!" Sherlock protested. "Mummy said not to close us out!"

"Mummy said not to shut the door," Mycroft argued coolly, "And she also told you, young man, not to disturb me while I'm doing my homework. Now don't pout! Go play with Angeline."

"But we want to play with you, Myles!" Sherlock pleaded, using the nickname his little sister had given his brother.*

"I'll play with you after I'm finished with my work." the door now properly patched up, Mycroft stood and walked back to his desk.

"All you ever do is work!" Sherlock yelled angrily through the duct tape. "You're gonna grow fat, sitting at your desk all day!"

"Go!"

It wasn't a shock that Sherlock returned to pester him, this time dragging their baby sister along with him. Mycroft could hear them coming down the hall, having the same argument he'd heard a hundred times at least.

"Now what did I tell you, Angeline, about physical contact?"

"No hug Shurry?"

"Yes, that and my name is Sherlock."

"Shurry!"

Mycroft heard his little brother groan. "Sher-lock! It's not so hard!"

"Shurry's more fun though."

Mycroft heard Sherlock sigh but not argue, as they stood outside his door. "Let us in, Mycroft!"

"I'm still working," he protested. "Go play The Hobbit or whatever you want now."

"Hobbit!" Angeline squealed happily.

"We can't play Hobbit without Gandalf!" Sherlock argued.

"Gandalf doesn't go into Mirkwood, does he?" Mycroft reasoned. "Pretend you're traveling through Mirkwood."

"Alright," Mycroft thought his brother's voice carried a tone of craftiness, but he had no time to ask what Sherlock was plotting before he found out.

Mycroft heard a thwack, and looked up from his history book to see that his brother had ran into the duct tape covering the door, sticking himself to it.

"Sherlock! What are you doing?" he stood up.

"Help me, Bilbo! I'm stuck in the spider's webs!" Sherlock cried.

"Bibbo save you!" Angeline screamed.

"Wait, wait, where are you going?" Sherlock shouted after her.

Mycroft sighed and sat back down. "Now you've done it, Sherlock."

"Well are you going to help me out?" Sherlock asked.

"And take the adventure away from Bilbo?" Mycroft smirked. "I wouldn't dream of it."

Sherlock huffed. "Brilliant."

Just then Angeline came running back. "Bibbo got Sting!"

"That's not Sting, Angeline, that's just an umbrell- OW!"

"Bibbo sorry."

After allowing the two of them to struggle for a while, Mycroft got up and ripped the tape from the doorframe- and his little brother.

"Ow!" Sherlock yelled.

"Shurry and Gandalf are free!" Angeline clapped her hands.

"Quick, run in before he shuts the door again!" said Sherlock, ducking into his brother's room and making a beeline for the desk. He hopped onto Mycroft's desk chair and began examining the papers. "Hey!"

He looked up to see his brother grinning mischievously. "You're all done!"

"Maybe if you'd waited a few minutes more instead of getting yourself trapped, I would've come out sooner." Mycroft shrugged.

"Gandalf play with us now?" Angeline looked up at Mycroft.

"I'm hardly a proper Gandalf, I don't have a staff."

"Use that stupid umbrella," Sherlock grumbled, rubbing the back of his head as an afterthought.

"But that's Sting!" Angeline hugged the umbrella close. "Myles can get his own 'brella!"

"Use my plastic sword for Sting." Sherlock suggested.

Angeline's eyes widened. "But Shurry said no touch pirate sword."

Sherlock sighed, leaning back in his chair. "Just this once. And only this once, do you hear?"

Mycroft raised his eyebrows as Angeline ran off giggling with glee. "You really want to get that umbrella out of her hands, don't you?"

"That umbrella is dangerous!" Sherlock glared at the umbrella in question, left at Mycroft's feet.

"So why do you trust me with it?" Mycroft smirked.

"Who doesn't trust Gandalf?" Sherlock's eyes glittered with amusement.

Angeline ran back in, swinging her brother's toy sword. "To the mountain!"

"Wait, I have to get there first!" Sherlock eased himself to the ground and ran past his siblings.

"I'm gonna catch you, Smaug!" Angeline hollered, turning to chase her brother down the hallway.

"That's not what happened in the- OW!"

* Okay, that headcanon I did come up with: Myles is short for Mycroft. When Angeline had the twins, though, Sherlock blatantly forbade her from naming her other son after him, so Beckett it was. Why Beckett? Because, dear Sherlockians, Beckett is an English name that means bee farm.

A/N: Well that's our little piece. Sorry the pirate thing and the bees thing weren't used more; they've grown into fanon, and we had already planned this bit around The Hobbit. We are also looking for canon support for the bees thing What do you guys think? Should we plan on a chapter two?