The shrill of the doorbell ripped the doctor from his sleep in a blind panic. His years of service had definitely changed him. His heart was racing and an instant sweat had broken out across his skin. He swallowed to slow himself down.

He managed to pull himself out of bed at the demand of the bell. It was still ring like a child was playing with it. The doctor grumbled as he hobbled towards the door, this better be important and if Hamish was awake then he'd literally kill someone- most likely the person at the door.

"Yes?" He hissed sourly before he'd even opened the door fully. The doctor usually prided himself on his good manners and caring quality but at 3am anyone would be grouchy.

The visitor strode into the house with a steady stream of words falling from his lips like smoke. The homeowner had to snap himself out of his sleepy daze to understand why someone was entering his home.

It was Sherlock, the tall, clever detective from Lestrade's crime scene earlier today. The acquaintance found his way to the kitchen easily and began pulling mugs down from the cupboards and setting them down in the work surface. His slim fingers flicked on the kettle.

The patting of feet made the young man freeze and his cool eyes widen. His words stopped flowing as all senses moved to the sudden new addition to the room.

"You have a child." His eyes scanned the room. Seemingly cataloging useless pieces of information. "How did I not realise?"

The ex-soldier shrugged before leaning down to pick Hamish up. The small boy was disheveled from sleep and was rubbing his tired eyes. The doctor settled his son against his hip. His small hands held on tightly.

The detective turned and his sharp scrutiny was instantly on the small human. His eyes studied the young boy as though he was a corpse at a crime scene.

"You thought he was a dog." John chuckled, resting his cheek against the top of the boy's bright blond hair.

"Where's his mother?"

"Lots of people don't have mummy's." The quiet voice broke over the tense silence. Even when John and Sherlock couldn't find the words, the young boy could.

There was a brief second when Sherlock's eyes scanned John again, this time clearly selecting some specific details from his body and face. An acute line formed between his brows. He'd seen John's bisexual from the moment they first met but now he knew he must have missed other important facts if he'd overlooked the boy.

John seemed to hold his son closer to his chest, almost protectively, "Why are you here, Sherlock? What do you want?"

"His father?" Sherlock asked, his tone was tense.

"Sherlock." John hissed, darkly. "I think it'd be best for you to leave now." Hamish had buried his face into his father's shoulder, upset at the detective's questions over his Daddy.

Sherlock looked baffled at John's insistence that he left. He opened his mouth with a comeback ready on the tip of his sharp tongue but John beat him there.

"No, Sherlock." He led him towards the door, "I'll see you some other time. Please do not come here and upset my son ever again."

He gave the taller man a sudden shove sending him out onto the cold corridor.

The detective peered up at the dull door with a sigh. He wasn't going to test John and push his boundaries; he already trusted the doctor too much. He turned and slumped back towards the dark outside world.

"Papa, who is the man?" Hamish dared to ask once John carried him back towards his small room.

The doctor sighed, "It's Sherlock. He helps Uncle Greg sometimes."

The small boy seemed confused but allowed the doctor to tuck him under the blankets, "Why does he want Daddy?" Scared eyes were pinned to his father.

"Lots of children have two parents, Ishy. You only have one now so he asks where your Daddy is."

The boy's voice is whisper soft, "But you said Daddy not coming home."

"That's right, Baby." He kiss his son's forehead, "It's just me and you now."