Mycroft Holmes was visibly upset. Or the closest Mycroft had ever been to being visibly upset. He had abandoned his suit jacket and umbrella and was bracing himself against the kitchen table, taking a deep breath as Sherlock pointedly ignored him. Apparently he had something much more interesting under the lens of his microscope.
John froze in the doorway, the shopping in one hand and Jack on his hip. Mycroft tensed as Jack squirmed down from John's grip and bounded over to him, wrapping his arms around his leg. "Uncle Crofty!" Mycroft extracted himself from Jack's grip and turned to John, his face stone. Jack, undeterred, circled around Mycroft. "Are you made at Sherlock too? Everyone is mad at Sherlock."
"Mycroft is going to ask you to remove Jack from the room," Sherlock drawled, adjusting a knob on his microscope. "It's absurd, of course, and you won't do it. I must thank you for taking such pristine care of my microscope, John."
Mycroft's jaw worked for a moment as John brushed past them both to put away the shopping, Jack trailing after him. "Stop blathering on about your blasted microscope and listen to me Sherlock," he hissed, and John had never heard Mycroft so furious. "I have expressed to you how dangerous this situation is. People are going to want revenge, and you are willfully giving every one of them the ideal ammunition. It would be better for everyone involved if you just accepted what I am offering you and your doctor."
"Could you show Mycroft to the door please John?" Sherlock said lightly, tapping the counter with his fingertips impatiently. "He's being characteristically redundant, and I cannot abide his company a moment longer."
Mycroft took a deep breath, the vein over his temple throbbing. He looked very much like he could throttle Sherlock if he allowed himself to, but he never would. "I tried my very hardest to teach you how to function in society, Sherlock. I did the best that I could, accounting for our...deficiencies. I had everything at my disposal- therapists, doctors, psychologists, anything that could possibly help you- and it wasn't enough. If that child were to be examined, doctors would find similar developmental benchmarks. Do you really feel that you are capable of teaching a child that undoubtedly has antisocial personality disorder how to be a human being when you have no familial obligation to do so?"
Sherlock hands stilled, and he turned towards John. Jack was in his arms, frowning at Mycroft as he nibbled on a Jammy Dodger. "If anyone is capable of saddling Jack with a diagnosis of any sort, it is John. He's the doctor, Mycroft, as much as you'd like to think yourself one," Sherlock spat, not even glancing towards his brother. "You've plenty of experience diagnosing me with any number of illnesses to explain away your utter failure to correct my 'deficiencies', but that does not a doctor make. John, in your expert opinion, does Jack have any mental disorders that you have noticed?"
John swallowed thickly, shaking his head a bit. "No, he's developmentally advanced, but there's nothing to be concerned about. Just because...Mycroft, you can't think that he's bound to be a...to be a murdering psychopath just because of his genes. The science just doesn't support that. Millions of murder cases don't support that." He put Jack on the floor and shooed him towards the living room.
Sherlock began unrolling his sleeves with sharp precision, his eyebrows raised. "My doctor seems to suggest your observations are irrelevant, Mycroft, I would suggest you heed his diagnosis. I am well aware of the fact that I am not equipped to raise a child. That's why I have John. He's been quite successful thus far. I believe that I was still refusing to talk when I was Jack's age. If you are planning on breeding, Uncle Crofty, I would suggest you ask John for child-rearing advice. Good day, brother mine. You've worn out your welcome, I think you can show yourself out. John really must be starting Jack's dinner."
Mycroft's face was pale. He worked his jaw, and he straightened his spine. He snatched up his jacket and shrugged it back on, his gaze level on Sherlock. "I do hope that John has better luck than I ever did. I expect that Jack will be grateful for all that John has sacrificed for his well-being."
Mycroft felt a gentle tug at his trouser leg and he looked down. Jack was holding his umbrella out for him, and Mycroft took it with a barely perceptible nod. "If you find yourself needing to fake your own death again anytime soon Sherlock, don't hesitate to contact me. I'm quite capable of making people disappear."
"Get out," Sherlock snapped, but Mycroft was all ready gone.
Jack was feeding Puppy bites of all the various foods on his plate, frowning when he didn't eat any of the tinned tomato, steamed broccoli, or bread. Jack was about to slide the rest of his fish into the floor when John finally caught on to what he was doing, taking his plate away and cleaning up the mess. "He's experimenting on the cat, Sherlock. You haven't been experimenting on Puppy in front of Jack, have you?"
"I have been trying my very hardest to forget about the cat's existence," Sherlock called from his bedroom, where he was sorting through his things.
John sighed, picked up the cat, and put him outside the door, shooing him down the stairs towards Mrs. Hudson's flat. "You do realise you can't bring anything hazardous or breakable into the flat proper. Anything that falls into those two categories must stay in your room."
John could hear Sherlock grumbling from the depths of his room. "I'll have to be rid of the bed. Would you like this one? It's larger than your current bed, maybe Jack can have yours, I'm sure we could find a way to make room for both in your room."
John wiped Jack's hands before setting him loose. He went straight for Sherlock's room, hesitating only briefly in the doorway before going inside. John followed quickly to make sure he didn't pull over any boxes on himself. "I'm not taking your bed Sherlock," John said, frowning at the stacks of files on Sherlock's obviously unused bed. "You need a bed, you can't just convert your room into a lab."
Sherlock placed his hands on his hips, frowning at the boxes stacked along the walls. "It's the logical solution. I need a lab and Jack needs a play area that isn't hazardous, at least until he's old enough to understand what can and cannot be ingested. I sleep at odd hours that tend to not overlap with when you sleep."
"You mean regularly?" John asked, but Sherlock waved him off.
"I can't see a problem with having a bed that we share. If you have an aversion to it, or are sentimentally attached to your bed, we can reconsider, but I am merely..."
"Shut up Sherlock," John sighed, and Sherlock finally looked at him. "We can move your bed to my room if you think it will help. It would be a shame to toss out a perfectly good bed."
Sherlock nodded once and clapped his hands together. "Right. I'll have to text Lestrade, tell him I'm indisposed for at least a week. We really should get started as soon as possible."
"Your room is messy," Jack added, peering balefully at the papers covering the bed. "And it smells funny."
"It smells like science," Sherlock said with a wild grin. "Go make room, John. If I can get the bed out of here I can spend the night unpacking boxes."
"Jack, if I put in a movie will you sit quietly and watch it while I help Sherlock carry out his ridiculous plan?"
Jack pressed his hands together, his grin eerily like Sherlock's. "Bambi! Bambi! Bambi!"
"Bambi it is," John said, and Jack tore out of Sherlock's room towards the living room.
"What sort of burgeoning psychopath is a fan of woodland creatures?" John chuckled before following.
"They do tend to favour Machiavelli," Sherlock added, transferring the files to the floor. "At least at that age."
