Sherlock was woken at 3AM, not by a "Dah!" but by the cries of his son.

"Hamish? Are you alright?" He shot out of bed and pulled his son's small and very warm body to his chest.

Hamish simply continued crying as Sherlock examined him. High fever. Possibilities: sore throat, headache, earache, stomach pain. Further data required.

"It's alright, Hamish, everything's alright, I'm here now. I need you to tell me what's wrong." He held the toddler's feverish head to his shoulder as he swayed gently on the spot, hoping to calm him down.

Once Hamish's cries had been reduced to hiccups and sniffles, Sherlock carried him to the bathroom, sitting him on the counter. "Is it hurting, Hamish?"

"Mhmm."

"Where is it hurting? Your head?"

Hamish gave a little nod.

"Does your throat hurt? Does it hurt here?" He placed a gentle finger on the boy's throat and Hamish nodded again. "Anywhere else? Your stomach?"

The toddler looked confused.

"Your tummy, Hamish." John stood in the doorway, rubbing the sleep from his eyes.

"No," Hamish said softly.

"What about your ears? Can I have a look at him, Sherlock?"

The detective stepped aside, and John pulled his medical kit out from the little cupboard beneath the sink.

"Yes," the little boy said, pulling at his ear with one hand.

"I knew he'd get sick," John said as he tried to put the thermometer near Hamish's ear.

"No, John. No!" Hamish pushed his hands away with his own tiny and, now that John looked at them, trembling, hands.

"It's alright, Hame, it won't hurt you. It's very quick."

"No!"

"Alright, shhh, it's okay. We can use this one; it goes under your arm."

"Kay."

"He's shaking, Sherlock, the fever's really high. We might have to take him to the hospital. Can you run a cool bath for him?" John said calmly.

Hamish suddenly started crying again and John pulled him into his arms, careful not to dislodge the thermometer.

"Shhh, Hamish, it's okay. You're going to have a bath to make you feel better," he said softly as Sherlock hurried to run the bath.

The thermometer beeped and John laid Hamish on the change table, pulling off his little jumpsuit and swearing under his breath when he read the temperature.

"It's 104. We'll put him in the bath and give him some paracetamol and if it doesn't go down in the next hour we'll have to take him to the A&E. You want to go in the bath by yourself, Hame?"

"Kay."

"Good man."

He let out a little whimper of protest when he was placed in the bath, the water feeling freezing on his hot skin.

"It's alright, Hamish." John ran a wet washer over the boy's hair and face while Sherlock measured the paracetamol out into a syringe. "Thanks, Sherlock. Hame, I need you to take this medicine for me, it will make it stop hurting, okay? I'm going to put this in your mouth and you need to drink it all."

"Kay," Hamish croaked, opening his mouth.

He coughed when the first little squirt entered his mouth, crying when this hurt his throat.

"Oh, Hamish, I'm sorry it's hurting, little man. Can you try again for me?"

"No. Dah."

Sherlock's voice was the gentlest John had ever heard it. "It's alright, Hamish, I'm just here. You need to listen to John because he's a doctor. He knows what to do. He can make you feel better." The detective knelt down next to the bath and placed a calming hand on the back of his son's neck.

"Try again, bud." John cupped his little cheek in one hand while he held the syringe to his mouth with the other.

After sitting in thought for a moment, Hamish opened his mouth, leaning into the warm hand on his cheek, and dutifully swallowed the medicine.

"Good boy. Well done."

"Hurt." His eyes filled with tears again.

"Did it hurt you?"

"Mhmm."

"I promise it will make you feel better soon, Hame."

"Out." Hamish tried to pull himself up, only to be gently pushed back by John.

Sherlock ran a hand over the boy's curls. "Hamish, you just need to stay in for another little minute, alright?"

"No. Out."

"Just one more minute, Hamish. Do you want your boat?"

"Kay."

They managed to stretch him out for another few minutes and then John pulled his shivering little body close, wrapping him in a towel. The toddler suddenly looked rather delirious, staring vaguely at the wall, his head resting on the doctor's shoulder.

"Alright, Hame?"

"Mhmm."

"Does he feel cooler?" Sherlock hovered in front of them, worry etched across his face.

"A little. Hamish I'm going to take your temperature again, okay?"

He simply nodded, placing his full weight in John's arms.

"103.2. It's gone down a little bit. I need you to have a drink of water, alright, Hame?"

"No, hurt."

"It will hurt your throat a little bit but it will stop your head from hurting," John explained as he put a nappy on the toddler.

"Dah." John had never seen a child look so miserable. Hamish's blue eyes were red and puffy from crying, his cheeks were flushed but beneath this, his skin was a sickly white.

"Here you go, Hame," he said as he passed him to Sherlock. "Now come on and we'll get you a drink."

As John was pouring cold water into a kiddie cup, he heard a small cough, followed by an, "Oh, Hamish," from his flatmate. When Sherlock entered the kitchen, the toddler still in his arms, he had vomit smeared across the front of his t-shirt.

"Soh, Dah."

"No, Hamish, it's alright, there's no need to apologise. I can just change my shirt, it's not a problem."

"Hurt," Hamish whimpered.

"Did it hurt your throat?" Sherlock asked as he ran his fingers through the boy's hair.

"Mhmm," he nodded and pointed to his head.

"It hurt your head as well?"

"Mhmm."

John handed Hamish the cup, which he slowly brought to his lips, cautiously drinking the water. "Can you bring him into the clinic in the morning, Sherlock? I'm working from 8 until 2 so you can just bring him to see me. I think he's definitely got tonsillitis and it's difficult to tell if his ear's infected as well or if it's just referred pain from his throat. I'll need to look at him properly at the surgery. Do you want something to eat, Hamish?"

"No. Bed."

"Yeah, that's a good idea."

Hamish slept on Sherlock's chest for the remainder of the night, the detective checking his temperature every half hour. They left early to get into the surgery before it opened.

"Jesus," John sighed as he put his otoscope down. "Double ear infection and tonsillitis. No wonder you feel so bad, little man. We'll pump him with antibiotics but he's going to be really sick like this for at least a few days."

The toddler was sitting on his father's lap, leaning heavily against his chest.

There was a small knock at the door and Sarah poked her head around the side. "Oh, sorry, am I interrupting?"

"Not at all. Come and meet Hamish. He's quite sick today, unfortunately." John smiled at the little boy, who was pulling on his ear with one hand, trying to stop it from hurting.

"Hey, Sherlock. Hello, Hamish. I'm Sarah. Oh, look, he's beautiful, Sherlock."

"Dah," said Hamish, pointing to the detective.

"Is this your Daddy?"

"Mhmm."

"What's wrong with him?" She looked between John and Sherlock.

"Hurt," Hamish answered her.

"What's hurting you, darling?"

He pointed to the various affected areas with a frown.

"Double ear infection and tonsillitis," John explained.

"Oh, you poor little thing, you must feel awful. John, we'll be okay without you today. Sick kids are a two person job. Take the rest of the week off, and ring me if you need more time."

"You sure?"

"We'll be fine."

"Thanks, Sarah. He had a really high fever in the night and I just…"

"It's fine, John, go home. I hope you feel better soon, Hamish."

"Bah," Hamish said, waving weakly.

By the time they got back to Baker Street, Hamish was so exhausted that he couldn't even cry anymore. He would simply loll around in whoever's arms were holding him at the time.

John was currently cradling him in the crook of his elbow, as if he were a very small baby, while Hamish lay in a state somewhere between consciousness and sleep. The doctor swayed from side to side, the gentle movement placating the little boy while Sherlock paced.

Hamish would occasionally whimper out a random "John," or "Dah," but other than that the flat was silent.

"Why can't you fix it, John? You're supposed to be a doctor," Sherlock suddenly hissed at him, turning around from where he had stopped by the window.

"Sherlock, I'm doing everything I can. I'm sorry that I can't fix this straight away, I hate seeing him like this. But I've put him on antibiotics and we're just going to have to wait this one out," John said quietly, careful not to disturb the tiny boy.

"But look at him."

"I know."

"What is the matter with my nephew?" If John didn't know better he would have said that Mycroft looked… concerned.

"Why are you here?" Sherlock sneered, glaring at his brother.

"He has an ear infection in both ears, and tonsillitis," John explained, running a gentle finger along the boy's nose, trying to get him to sleep.

"Oh dear."

"He's never been exposed to germs before, Mycroft. That's why he's so sick. His immune system is useless. We're actually lucky he's not worse." The doctor frowned, sighed, and returned to comforting the little boy to sleep.

"I am sorry to hear that."

"My?" Hamish's croaky little voice piped up. He had reached a moment of almost-lucidity and recognised his uncle's voice.

"Hello, Hamish," Mycroft said quietly.

"Would you like to go to Mycroft for a little minute, Hame?"

"Mhmm."

Mycroft carefully held the toddler against his chest; a comforting hand ran over his curls as he sank into the tall man's arms. Hamish wrapped a small hand around Mycroft's lapel and the elder Holmes carefully sat on the sofa.

"I'm going to get you a little drink, Hamish," John said on his way to the kitchen.

"He has a fever," Mycroft announced.

"That's nothing. It's only just over 100 now. It was 104 in the night; we almost took him to the A&E." John stirred some honey into a kiddie cup of warm water with some honey stirred into it. "Here you go, Hame. Drink some of this for me, okay? It will make you feel better. And you can have some ice cream afterwards if you want."

Hamish was dubious. Every other thing John had claimed would make him feel better had simply made him even less comfortable. The bath had made him feel colder than he already did, and that horrid medicine he kept giving him hurt his throat.

The first gulp of this did hurt him, but, always determined, he persisted. After the initial sip, a protective film formed around his throat, finally soothing it.

He hummed and smiled gratefully at John, resting his head against his uncle's chest. "Ta, John," he whispered, before falling asleep, cup still in his little hand.

"Finally," Sherlock sighed.

"We've been trying to get him to sleep for hours. He's just so uncomfortable that he can't relax."

"I'll put him to bed," said Sherlock, carefully pulling his son's limp body from Mycroft's hold and carrying him into the bedroom.

Hamish slept for almost four hours with Sherlock obsessively checking his temperature every fifteen minutes. The detective's pacing was driving John a little bit mad but at least he wasn't complaining that he was bored.

The little boy woke up crying and threw up all over John when he was pulled from the cot, only causing him to cry harder.

"Oh, Hamish. It's alright. Settle down."

"Dah," he sobbed, clutching at John's shirt.

"Shhh. It's okay, little man," John rocked him back and forth as he carried him to the living room, passing him to Sherlock and disappearing upstairs to change his clothes. "This is awful," he said on his return.

Sherlock was standing in the middle of the room, Hamish once again cradled as if he were a baby, trying to stop his crying. "This is the worst day of my life," the detective said solemnly as he brushed the stray curls off of his sons' forehead.

"I just wish I could do something for him. It was good of Mycroft to come. Hamish was glad to see him."

Sherlock frowned. "Yes. I'm not sure what we can do about that."

"Sherlock, there's nothing wrong with… never mind. It's time for some more medicine."

"His head's healing up nicely."

"Yeah," gently John pried the little boy's mouth open and slipped the syringe in. He was now only half-conscious so it was much easier to administer the medicine. "Hamish, I need you to drink this medicine, okay?"

"No." He tried to push the syringe from his mouth, but John pressed on.

"Shhh, Hamish, it's alright. John's helping you," Sherlock said gently, holding Hamish's hand.

"Do you want some ice cream after this, Hame?" John asked.

"Mhmm."

"Good man."

He swallowed the medicine, pulling a disgusted face at the doctor, which Sherlock laughed at, before sinking back into his father's arms.

"How about we watch some TV while John gets your ice cream?"

So they sat and watched Thomas the Tank Engine, Hamish spilled chocolate ice cream in Sherlock's lap, then he cried and apologised before forcing Sherlock to change his trousers with a series of insistent, 'Dah!'s.

Mrs. Hudson brought them up a casserole for dinner and held Hamish while John practically force-fed his flatmate who hadn't eaten anything since the day before.

"Would you like a bath, Hamish?" He'd started crying halfway through their dinner and Sherlock had jumped at the opportunity to not eat anything else.

"Mhmm."

"You would?"

"Mhmm. Ham."

"Yes, just with Hamish."

His fever had settled so John ran a warm bath for him, hoping it would soothe him enough that he would sleep. By the time Sherlock pulled his little body from the water; Hamish was so drowsy he could barely hold his head up.

"Hopefully he'll be able to just sleep tonight. Tomorrow will be better, Sherlock."