Author's Note: Hello everyone! This is my third kidlock story, but I suppose it's the first chronologically. It's a silly little idea that my best friend and I came up with while we were on holiday in November and I've been promising to write it. So Lauren, this is for you. I've written Sherlock this young, but the youngest I've ever written Mycroft was 14, so this was a bit of a challenge. It was a lot of fun though. I really hope you all like it! Please read, review, and enjoy!

Disclaimer: Clearly I don't own Sherlock. The show is the baby of Steven Moffat and Mark Gatiss, while Sherlock Holmes itself is the creation of Arthur Conan Doyle.

Four Minus One – By Blood-Sucker-1428

It was a Saturday morning – a time that the family was supposed to spend all together eating breakfast. It had been that way for seven years and was supposed to be that way forever. Yet it was Saturday morning, and for the forth Saturday morning in a row, Mummy was too busy dealing with the new baby to even spend a single minute at the breakfast table. Instead of nine o'clock pancakes, or eggs and toast, or even fruit for heaven's sake, it was now about eleven and father had only just emerged and pulled out a box of cereal. Cereal. No, Cereal is what Mycroft ate for breakfast on weekdays. On weekends Mummy or Father cooked, Mummy told Mycroft about all sorts of things, and Father read the paper and made the occasional joke.

That baby, William, or Sherlock, or whatever they'd decided to call him, he wasn't supposed to change anything but in one month he'd already changed everything and Mycroft didn't like it. Sure, it was kind of cute in a small wriggly kind of way, but it was noisy, demanding, and stole his parents. His parents had promised him, promised that this baby wasn't going to change his life, that he wasn't being replaced. But if that was true, then why all this recent neglect?

Mycroft sat at the kitchen table, arms folded tight against his chest, scowling as he watched Father pour the milk into the boring bowl of cereal. His dad gave him an exhausted smile as he turned to put the milk in the fridge. Mycroft used his spoon to scoop up some of the cereal, bringing it closer to his face for further inspection. He stuck his tongue out and dropped the spoon back into the bowl.

"What do you say, Myc?" The fridge door closed, and Siger glanced over at his eldest son as he walked over to make himself a coffee. Of course, because that baby had been keeping Father up, too. Father who worked during the week and had limited time with Mummy and Mycroft anyway.

"Thank you, I suppose…" Mycroft mumbled, folding his arms across his chest once more, pouting. Siger turned around to look at his son carefully.

"Is that really how you say thank you?" He questioned. Mycroft glared at his cereal.

"I don't want this." Mycroft whined. "It's Saturday. Mummy promised us eggs and toast. She promised." He'd stomp his foot if he could reach the ground. Siger's face softened. He walked over and, with a heavy sigh, came to sit down at the table next to his son.

"I know, Mycroft, but Sherlock's being fussy this morning." He tried to explain, but it wasn't good enough.

"He's fussy every morning!" Little Mycroft looked up to his Dad with his steel blue eyes. "He's fussy all the time."

"He's a baby, Myc." Siger leaned in closer. "You needed lots of attention as a baby, too."

"I don't think so…" Mycroft pouted, turning way. Somehow that caused Siger to chuckled and pat his son on his head. Irritated, Mycroft immediately fixed up his hair. He hated when his father did that. "You promised I wasn't being replaced." He'd asked them straight out if he had been a failed prototype, if he wasn't what they were looking for in a child and therefore wanted to attempt again. He'd given them a chance to be honest without hurting anyone's feelings. They'd told him that they couldn't be prouder of him…

"You're not being replaced-"

"Then why does he get all your attention?" A pause as the exhausted father rubbed his brow. Serves him right for having another child when he already had one.

"Mycroft, we love you so much, but babies need all the care and attention that they can get."

"And a seven year old doesn't?" The question had caught Father off guard as he stumbled and had to stop to think. She sniffed a laugh and shook his head.

"You're too smart for your own good." He smiled. "Babies need constant attention because unlike you or me, they can't look after themselves. They can't ask if they can go to the cupboard and open the cookies. They can't even open the cupboard." Mycroft rolled his eyes.

"Obviously, that would absurd." His choice of vocabulary made his father laugh and ruffle his hair again. Ugh. Mycroft quickly smoothed it over.

"Tell you what, after you eat why don't we get a book to read, or you can beat me at some chess? How does that sound." Mycroft chewed on his bottom lip, brows pulled into a frown.

"Promise?" He looked deep into his Father's matching eyes.

"You bet." The little boy nodded.

"Okay…" He muttered quietly. It was no breakfast with Mummy, but time with Father was better than nothing.

Then the wailing of the creature because louder and more piercing.

And then Mummy groaned.

"Siger dear, I need you." Mummy's voice came through the hall. Mycroft's eyes shot to Siger. The man shrugged and sighed.

"I better go help you mother." He forced a smile. Mycroft quickly took hold of his hand.

"But you said we could spend some time together." He pleaded, sounding far too needy.

"We will, pal, but after. Okay?" Mycroft dropped his father's hand limply.

"Okay…" And his father too disappeared out of the room to assist the baby.

Mycroft Holmes was all alone. He sat there, glaring at his soggy, boring cereal, listening to the faint sounds of his parents talking in sickening sweet voices to a creature that didn't even understand them while he was he and willing to put up with whatever boring stuff they wanted to talk about.

Not replacing him. Yeah, right. Apparently somewhere down the lines Mycroft had failed as a son. Maybe they were disappointed that he didn't like sports, maybe he was supposed to learn German before he started French… maybe he wasn't cute enough, or enough like the other little kids in the family. Something wasn't right with him, because his parents had promised that there was enough love in them for two children, but this Sherlock got it all. Maybe they hadn't lied, maybe they did have enough love for two, but only wanted to give it to the new one. The one yet to disappoint them.

It wasn't fair, it just wasn't. Mycroft was smart, he knew he was smarter than any other kid. He was polite to adults and stupid people, and he did what he was told. Any parent should be lucky to have him. There were couples out there who couldn't have children who would have loved to have what his parents consider the failed prototype.

Mycroft sat up straight in his chair, eyes shining bright, brain ticking fast.

That's it! There are plenty of people out there who would love to adopt Mycroft as a son. He could be someone else's prodigy, and they'd love him and spend time with him. There's no way they could replace him. Brilliant! He'd get up, leave, find new parents, and everyone would be happy. Violet and Siger could have Sherlock, and Mycroft could have people who appreciated him. All he needed was some resources.

Now, what did adults consider resources? Food and drink were obvious. Mycroft would just take his water bottle and put some crackers in his backpack, and that should last him until he found new parents. What adults found most valuable was money. If you had money, and a credit card, you could get yourself some food if you ran out, and buy books and puzzles, and bribe people. That could be handy. Lucky for Mycroft, Father's wallet was sitting right here in the middle of the kitchen table. The little boy got to his feet, standing on the wooden chair. He leaned across the table and pulled the little black wallet close to him. He pulled out all the notes and coins his father had in there, except ten pounds, he didn't want to look to conspicuous, and took one of his cards. He stopped to look at the little photo his father, soon to be ex-father, had in his wallet. It was a photo from Christmas when Mummy was pregnant. It was Mummy, Father, and Mycroft sitting on the bench together outside – Nana had taken it when she stayed Christmas Eve. Mycroft decided to take that photo, too. After all, why would Mummy and Father want it? They had a new son. Mycroft could keep this, you know… just as a reminder of where he came from.

He plopped back down onto the chair and then got up from the table. Now all he had to do was pack his backpack and he could go start a new life.

The seven year old child genius had managed to get very far on his own. He'd managed to get onto a bus by pretending to be with a mother and a bunch of little kids that were all handing their coins to the bus driver themselves. He'd then sat at the back with his head down to avoid being recognised by other passengers or any people who might drive past the bus who know Mummy and Father.

The train had actually been less issue than the bus had been. Out of the centre of the suburb, Mycroft didn't have to duck and hide and could walk around. As long as he looked confidant no one thought he was lost. He'd bought his ticket off a lazy worker. He'd bought one adult and one child with Father's money to make it look like he was buying for a parent. It got him in on safely on the train to London. London where the city was far too busy to notice a little kid wandering around on his own. London, with all the museums, libraries, and galleries. He could find a nice cultured family here.

There was a problem, though, as Mycroft looked around the dirty streets, knees rushing by him at all different speeds. As smart as Mycroft was, and as quickly as he committed items to memory, he'd only been to London a limited amount of times and only knew certain areas of it. He knew how to navigate from the train station to a few museums, and to Nana's house, and to Father's work… but he had no idea where to go to look for parents. This could present a little bit of an issue. But he'd gotten this far, hadn't he? And without so much of an issue. At this luck, Mycroft should have a new family by dinner time. He'd have a new surname, a new bedroom, a new Mummy and father, and a brand new life. It would be a shame, though. He so did like the surname 'Holmes', and Mummy was very clever… But it was too late for that, Mycroft wasn't good enough to be a part of that family. He'd find someone with a better name.

Alright, time to think. Parents take their kids to parks, no? Children usually liked to play. Maybe he could scout potential parents from a park, and he did know how to get to a nice one from here. Mummy had taken him to it about six months ago when they'd visited Father at work for lunch, and then they'd bought some new books to read. There had been lots of little kids with nice looking parents there. If he were honest with himself, Mycroft was getting a little hungry, too. He could go to the park, sit under some nice shade, eat his crackers that he'd packed, and look for parents. Yes, that would work nicely. A park would be good, much better than being accosted with all these fast walking adults.

The sun was beginning to set, creating an orangey hue in the sky above the London park. Not only was it starting to get dark, but it was also starting to get cold. Now, Mycroft was no idiot, he'd remembered to pack a scarf – which he was now wearing. The cold wasn't the issue.

The issue was that Mycroft had hoped to find a new home by the time the sun set. He had hoped to have dinner with nice new parents and go to bed in a nice warm bed. Well, that was a tad farfetched. They'd need time to buy a bed for a child – he'd settle for a couch on the first night. Mycroft had been sitting in that park for what had to be hours and there had been not one single acceptable adoptable parents.

No one had even come up to the intelligence level of Mummy, and not one of the men who'd stepped into the park looked remotely as kind as Father was. The other mother's spoke to their kids like they were idiots and Mummy never spoke down to Mycroft. Some were stupid, some were too fitness orientated, some had too many children, some would be okay if they weren't clearly homeless. One couple could have been okay, but from the way they dressed there is no way they'd spend time playing chess on the floor with him, or crouch of the kitchen table doing maths equations.

That was it, wasn't it? No one would be good enough to be his family because they weren't his family. He didn't share DNA and blood with these people, he had nothing tying them to him. Why would they love him when they didn't have an instinctual need to protect him? No, these people weren't going to be good enough.

But it was getting dark… and he couldn't go home… Mummy and Father had a new baby they loved. One that might play games and make them happy.

So what was Mycroft going to do? He was alone in the middle of the city and knew no one would be good enough to take him in but family.

…

Nana! Nana lived in London! Yes!

Family were the only ones obligated to love him, therefor family could take him in and love him enough. He could live happily with Nana.

Father's family would always be out of the questions. They spoke to him like other children. They bought him toys that not even an average four year old would play with, much less an above average seven year old. They gave him a football for his last birthday for heaven's sake. A football! He'd heard his uncle call him a little weird before. The adults hadn't realised he was listen. Father had gotten mad at that. Father had said "He's not weird, he's special like his mother. Don't be jealous because you dropped out of French and Violet and I can already speak to him in it." He'd told his father he loved him that night…

…

So, no, not father's family.

But Nana… Nana brought up Mummy. Nana knew what it was like to be a person of average intelligence bringing up a well above average child. She'd done alright with Mummy, after all. Nana never talked down to Mycroft, and she always listened to him. Every time they saw her they'd bake together and Nana would word the recipes like they were science experiments and it was fun and delicious at the same time. Sure, she was still slow and boring, but she was loving and Mycroft could be patient with her.

Mycroft knew how to get to Nana's from here. Most of the time when they came into London it was to get to Nana's. He could be there in no time. He'd show up, and tell Nana he was moving in. She'd be so excited that, unfortunately, she'd give him a great big hug. They'd have dinner, bake cookies, and then Mycroft could go to sleep in Mummy's old room. It would still kind of smell like home. He could be kind of happy there.

"Mycroft!" Nana practically wailed Mycroft's name as she opened the door. She quickly ushered him into her warm house that always smelt like cooking. The older lady dropped to her knees, and took the boy by his shoulder's, holding him out at arm's length. Mycroft knew she was looking him over for any signs of cuts or bruises. The adults always did that when they were in this level of panic. "How did you get here?" She exclaimed.

"I took the train." Mycroft smiled at her. He tried to peer past her into the kitchen to see if anything was cooking. He was starving.

"By yourself?" She asked, voice still loud and high, as she ran her thin hand over Mycroft's forehead.

"Yes." He asked, a little confused.

"Your Mummy and Daddy are worried sick about you!" Mycroft rolled his eyes. He pulled himself out of her arms and began to walk to the kitchen.

"No, they're not." He huffed, shrugging off his backpack and climbing into one of the chairs at Nana's kitchen bench. He could smell pasta. He could really use some pasta after only eating crackers today. Nana followed him into the kitchen and came to stand across from him. Mycroft shrugged and folded his arms across his chest. "They don't want me anymore so I thought I'd come live with you." The concern on Nana's face turned to pity, then to a deeper kind of worry.

"Why on Earth would you think your parents don't want you anymore?" Mycroft looked down to the surface of the speckled counter and shrugged.

"They have a new baby. They like him better." Nana clicked her tongue and 'aww'ed, and before he knew it, Nana had come across to the other side and pulled Mycroft into a big warm hug.

"Don't be silly, Mycroft. I love Sherlock, but I love you too." She let go of the young boy. "And I have it on good authority that your Mummy just adores you to pieces, and your Daddy is just impressed by you every single day." Mycroft tried to strong, but he felt his eyes grow heavy with tears that threatened to fall.

"Then why did they replace me?" The tears were definitely a mistake. It earned him a second hug, this time with a rub on the back.

"Oh, dear little boy." Nana cooed. "They didn't replace you." She pulled away to look into Mycroft's eyes with her eyes as sky blue as Mummy's. "They love you so much that they wanted another one of you. The only thing better than having one amazing little boy, is having two." She cocked her head to the side. "Do you understand?" Mycroft chewed on his bottom lips as he though. He nodded.

"It would make sense to want more of me…" He hummed. It certainly made more sense than not thinking he was good enough, and the world would gain from getting another Holmes genius… Even though they're not guaranteed another genius. Sherlock might yet turn out more like Father than Mummy. Nana was smiling at him now. "But they should have made sure they had enough time to manage two of us."

"They do, Mycroft." Nana sighed sweetly. "Babies take up a lot of time at first, but Mummy and Daddy will learn how handle it, and the baby will grow stronger. Plus," She nudged Mycroft on the shoulder. "I thought your Daddy already gave you a speech about being a helpful big brother." Mycroft nodded.

"I already said I'd help keep him safe." He admitted.

"And how are you going to do that if you live with me?"

A pause.

"I suppose you're right." Mycroft huffed, unfolding his arms. Nana squeezed him again. How annoying.

"So I'm going to call your parents and they're going to come get you, okay?" Mycroft peered over to the stove as he felt his stomach rumble angrily.

"Can't we have dinner first?"

Nana laughed.

Always one for dramatics, Mummy practically tore through Nana's front door. She looked panicked and her breathing seemed very erratic. Her bright eyes scanned the area to find Mycroft comfortably sitting on Nana's sofa. He through Mummy a small wave of his hand. Mummy walked fiercely towards him, her index finger pointed at his chest.

"You, young man!" Even sounding out of breath, angry Mummy was very frightening. She seemed to get so much volume. "Are in so much trouble!" Mycroft was too fixated on his approaching mother to see his father slip in with the baby behind her. As Violet got up closed to Mycroft she pulled him deep into her chest, resting her chin on his head. She began to sob, and Mycroft allowed himself to reciprocate the hug. "You scared me so much." She hiccupped between sobs.

"Sorry, Mummy." Mycroft muttered quietly as he gave her a gently squeeze.

"If something had happened to you I'd never forgive myself." She pulled him in tighter.

"I'm sorry, Mummy…" He repeated. She pulled him away, tear soaked eyes searching his face as she placed her soft warm hands on either side of his face.

"What on earth possessed you to run away?"

"I thought you didn't love me…" And he was cocooned once again in the protection of his mother.

"Don't be so stupid." She squeezed again. "I love you so much. You Holmes boys. You, your father, and Sherlock, are the most important things to me in the entire world. There is nothing I wouldn't do for you." She pulled away again, this time smiling. Once again she cupped Mycroft face as she sniffed. "Never do anything like that again, or so help me, you'll never see the light of day again." Mycroft sniffed a laugh and nodded.

"I won't." He nodded. Violet turned back to look over at her husband as she sighed the biggest sigh of relief.

"Where did he get such a dramatic idea from? Causing us all heartbreak?" Siger gained a small smirk as he looked down at his infant child in his arms.

"He gets it from you, dear." He chuckled lightly and touched to baby's nose. "If we're lucky, this one won't inherit the dramatics." Violet turned back to Mycroft, pulling on over exaggerated offended look, mouth agape, and hand held to her heat, and scoffed.

"Did you hear your father, Mycroft? How rude!"

At this point, Mycroft was too tired to really join in on his parent's antics. He just wanted to go home. He wanted to go to sleep in his warm bed that smelt of Mummy's laundry detergent, and wake up feeling like he belonged. Even if waking up was due to his baby brother crying. It's just something he'd have to get used to.

Author's Note: So there we have it! What do you think? I really hope you enjoyed it! We had a lot of fun coming up with ideas, and it was refreshing to write. I hope you think it was okay! Thanks so much for reading, and if you enjoyed it feel free to check out my two other kidlocks featuring kid Sherlock and teen Myc.