"I think I would be perfectly alright if you died," Sherlock said over tea. He glared at Mycroft and very deliberately took a sip of Darjeeling.
John stopped in the doorway of the kitchen, mug in hand. "Sherlock, for god's sake!" Tea sloshed over his hand and dripped down his fingers as he strode into the room and slammed the mug down on the coffee table. "That is definitely 'not good'!"
Sherlock's eyes flickered to John and he looked away.
Mycroft's mouth quirked at Sherlock’s expression. "Indeed?"
"Hmmm. Yes. I think about it at times, you know." Sherlock stretched his legs out and then got to his feet, dressing gown loose around him, ignoring John's increasing dismay. "Heart attack, or assassination, say. Maybe someone finally decides you are too smug to live and blows your brains out all across that dreadful Turner you have in the lobby."
"It’s a perfectly adequate representation of his later period," Mycroft said, and grimaced down at his teacup, setting it to one side.
Sherlock turned to John and mimed a gun to the head. "Boom. No more Mycroft." He shrugged and wrapped his dressing gown about himself. "If my brother had any consideration for those around him, that would be the way to go."
Mycroft rolled his eyes. "You're being childish, Sherlock, and worrying John." There was no hint of irony in his voice and John hesitated, tea in hand, unable to pinpoint why this sounded wrong.
"Oh, John doesn't worry about you. No one worries about you, Mycroft," Sherlock said with visible venom, and flung himself back down in his chair.
John was abruptly certain that he’d missed something important about this particular conversation. "Sorry, what?"
He wasn't even supposed to be here today. He had booked the day off to spend time with Mary and baby Charlotte, and instead had received a text from Sherlock peremptorily summoning him back to 221B. He had contemplated not going for all of 10 seconds, until Mary had raised an expectant eyebrow at him and he had yielded with good grace.
Instead of muggers, clients or head trauma, he had found Sherlock in a foul mood in the living room, glaring at a Mycroft who was examining his cuticles with exquisitely precise boredom. "I want tea," Sherlock had told him, not looking up from where Mycroft was still buffing his nails on the armrest of John’s chair.
John had gaped, his coat still on and the distinct smell of baby vomit clinging to his t-shirt. "Sherlock. I was in bloody Battersea!" In Battersea and with a baby asleep on his chest, to be precise, and had he honestly trudged across two entire zones to make his ex-flatmate a cup of bloody tea?
"I want tea."
"You could have called Mrs Hudson! Or, I don’t know, made some yourself!"
"Mrs Hudson is visiting her sister."
John had glared for a while, and then gone to make the effing tea, because there was no point shouting at the sodding tide. He’d brought out the tea set in deference to Mycroft's especially prissy expression, and then – once he had sorted out Her Majesty and His Highness with their First bloody Flush Darjeeling – had made himself a decent cuppa.
And had then promptly spilled most of it when Sherlock had decided to be even more horrifically inappropriate than usual.
"Sherlock. What are you – no. No, I’m not listening to this." He mopped up the spill with a dishtowel and grabbed his coat again. "If the two of you want to have a pissing contest, I'm going to just leave you to it."
"Sit down, John," Mycroft said, sounding supremely bored. "I'm sure my brother has some particular reason for wanting your presence despite my repeated requests to the contrary."
"I don't see why I should be obliging when you are anything but!" Sherlock bit out, pulling his legs up to hug his knees. He rather looked like a small child having a bit of a sulk, John thought.
"I have been perfectly obliging, Sherlock. I have even abided by your one exceedingly inconvenient request of me, much to my current dismay." Mycroft shifted a bit in John’s chair. "You can be certain I shan't make that mistake again."
Sherlock's eyes narrowed. "What did you just say?"
"Oh, for the love of God, would you two stop it!" John pulled his coat on. "Sherlock. I have made you your bloody tea, now if you don't mind, I am going to go back across the bloody river to see my baby, whom I haven't seen in quite some time because of the insane hours I have been working. I suggest that the two of you work out what it is that's making you so bloody childish and get it seen to!"
Sherlock turned to glare at him. "Sit down, John."
"Oh, now, really, Sherlock, if John wants to go –"
Sherlock jumped to his feet, his body taut with rage. "You! You just shut up!" Jabbing a finger in Mycroft's face, he turned back to John. His expression turned pleading. "John. Just – please. Sit down."
Please. Sherlock never – he didn't – Sherlock never said please.
John sat down abruptly, hitting the sofa more by accident than design.
Sherlock turned back to Mycroft. He looked angrier than John had ever seen him, and it made John's breath catch with the numbing realisation that he hadn't noticed it until this second. That he hadn't realised just how upset and angry Sherlock really was, when his lips were white with rage and every breath looked laboured with the effort not to hyperventilate.
"Have you told Mummy?" Sherlock said after a moment, dragging his dressing gown around himself with a contained, taut fury.
Mycroft looked down at his nails again. "Don’t be ridiculous, brother dear. There's no need to worry her when this little problem can be resolved so easily."
Sherlock's mouth thinned to almost nothing. "Easily," he said, as if it was an obscenity. "And the cost to me?"
At that, Mycroft looked up, real surprise on his face. "There is no cost to you," he said. There was a moment of puzzlement, and then it dissolved into that familiar smug smile. "Ah. Hence your anger. Yes, now I understand. No, you have, as they say, got the wrong end of the stick, brother dear. I have made alternate arrangements. There is no cost to you at all." He buffed his nails on his lapels once more, and moved to stand, his movements oddly jerky. "I think that –"
Sherlock pushed forward into Mycroft's space, crowding him back into John's chair. "Think?" He mocked quietly. "You think? You think you can come here, and tell me this, and then you think you can just – what? Get up and leave?"
John stared down at the mug of tea that he had somehow taken in his hands again. There was something very wrong here, from Mycroft's studied indifference through to Sherlock's uncontrollable rage. No, not just rage – there was real distress there. Fear. Whatever it was Mycroft had said, it had scared Sherlock to where he was lashing out in panic.
Whatever it was Mycroft had said to Sherlock, it was something he didn't plan to tell their parents about.
Abruptly, John noticed that Mycroft's perfect suit was sitting a little large on him, the collar of his shirt gaping just a touch. Mycroft's pale skin looked even paler in the morning light, a thin clammy film visible around his hairline.
Despite Sherlock's acrobatic histrionics, Mycroft had remained perfectly still in John's chair since John's arrival, except for that one small flinch when Sherlock had crowded his space. That one small flinch, arm instinctively curving around to shield his vulnerable left side.
John looked back down at the mug of tea, and set it carefully on the coffee table. He stood up and walked across to them, putting one hand on the back of Mycroft's chair. "How long have you been sick?" He asked.
Two pairs of eyes flickered to him in surprise. Mycroft's lips twisted in a smile. "I do keep underestimating you, John. It has become a bad habit. How did you know?"
John looked pointedly to where Mycroft's arm was still curved protectively over his left side. "I can see it. You're pale, and sweating – clearly this is a physical effort for you. Your suits are bespoke, but this one is too big for you, and your collar is gaping: you've lost weight recently and you're trying to hide it." He paused and nodded over to Sherlock, who was watching him intently. "And - Sherlock's upset. Not just having a sulk, but genuinely upset, about something neither of you want to tell your parents about. So unless you've taken up an unexpected substance abuse habit, you're sick."
Mycroft looked a bit discomfited. "I had rather hoped it wouldn't be that obvious."
Sherlock glared at him. "It's obvious to me. And John is a doctor."
Mycroft sighed. "And that's at least partly why you want him here, yes? I know. You don't trust me to be truthful with you. But I hardly think that an army surgeon – or a general practitioner – will be placed to tell you anything I don't wish to reveal."
Sherlock sat back down in his chair, folding his legs beneath him. He gestured expansively, narrowly missing knocking over his teacup. "Then you'd better reveal everything, hadn't you?"
Mycroft's look became more pointed. "As I have already made clear, I have made arrangements to have this little – complication – taken care of. I notified you because I had promised to do so, and because I had harboured a hope, however slim, that you might be a trifle more adult about it all."
This time the teacup did not escape unscathed. It crashed down on to the rug with another expansive hand gesture, the tea soaking into the pile. "Yes, because this is clearly my fault! For god's sake, Mycroft, why couldn't you have the good taste to just get assassinated like a normal spook!"
Mycroft took a breath. John took a breath. Sherlock took several, visibly trying to get his trembling limbs under control.
John rather thought that maybe he should stop this right now. This close, he could see the dark circles under Mycroft's eyes and the tell-tale hint of blue around his lips. Sherlock rather sounded as though he were hyperventilating; he, too, knew what he was looking at. John could see it in the way Sherlock's eyes were fixed on Mycroft's neck and wrists and lips and the thin shadows of bruising around the vulnerable joints; in the way that Sherlock's eyes followed Mycroft's every uncomfortable movement. Not a new illness, then; they’d been here before. Something that Sherlock had paid a dear price for, on behalf of Mycroft; something that he had found terrifying – and now, out of his infancy, still did.
John wondered how old Sherlock had been when Mycroft had been first diagnosed. How many treatments it had taken before Mycroft had finally gone into remission.
Sherlock muttered something under his breath.
"What was that?"
"I said," Sherlock repeated, glaring at the floor, "it’s stupid to find an 'alternative arrangement' when you already have a tried and tested method."
Mycroft closed his mouth after a moment. His eyes flickered to John helplessly, and John saw the truth of it: Mycroft had not expected this. "Sherlock," he said, soft and quiet, "I would never want that."
Sherlock looked up at that, and his eyes were wet. "What we want doesn't seem to be a factor in this, does it?" He looked to John and blinked rapidly, the glassiness easing a little. John nodded, offering silent comfort. Sherlock took a breath. "Your immune system accepted my bone marrow before. It's… it's stupid to take the risk with another donor. We'll do what we did before."
Mycroft looked away, but not before John had seen the answering glimmer of wetness in his eyes. "I would never ask."
Sherlock looked mutinous, as if Mycroft had physically wounded him by making him answer. "You would never need to." He looked to John. "And John will supervise."
John blinked. So that's why – well, of course. But - "no – wait. Wait, no. That won’t work. I'm not an oncologist."
"I trust you," Sherlock said. He nodded at Mycroft. "I trust you to tell me if there is anything he is trying to hide."
Mycroft regarded the ceiling. "That would be counter-productive. I'm not as obstreperous as you, brother mine."
Sherlock's smile was razor thin. "Brother mine, you only came to me after you'd made arrangements for an alternate donor. Despite the risk in delays, and despite the possibility of rejection. I suggest you don't dig yourself any deeper." His gaze flickered across Mycroft's form, lingering on where the tailoring revealed the rapid weight loss. "And during your treatment, you'll be staying – where?"
"At home," Mycroft said, in a tone that brooked no disagreement.
"Excellent," Sherlock said with false heartiness. "That Chelsea townhouse monstrosity you call a home is big enough for all of us."
"All – of us?"
John had a fairly good idea of where this was going, and a fairly insistent headache that was inversely proportional to how well he thought it was going to go.
"Well, you, me, the nursing staff – I'm not doing anything involving sponge baths – and I expect your assistant will insist on being available 24/7 as well during your convalescence, she is disturbingly devoted to you." He raised an eyebrow. "Unless you think she'd like to help with the sponge baths?"
"You will not be moving in –" Mycroft started, real horror in his eyes.
John's headache tipped over into migraine territory.
Sherlock's smile was, for the first time that day, genuine. "Try and stop me."