A/N: I'm SO SORRY this took forever to get up; I've had the worst case of writer's block. :-_- But here it is ,at last, the final chapter of the second in this series. Thanks to all of you for sticking with me through it and for being such great reviewers!

Chapter 6

It doesn't take him long to realize that Sherlock has far more sensitive- well, senses- then most people.

It takes him far longer to figure out what to do about it.

It starts the first time they have to weather a storm.

Lightening, thunder, the steady pounding of rain and the howl of the wind; Mycroft seems enraptured by it all. He sits by the window, all curled up, his (still too heavy, and not shrinking any time soon no matter how much John tries) frame tucked in upon itself, his gray eyes distant and far-away. Nothing in his hands, he seems content to stare out at the magnificence and power of the storm.

John himself has always loved them; they are wild power, strength- utterly untamed and unpredictable. They put him in mind of an animal, or perhaps of simply a different place then London, a place without it's constraints and rigidity. Not that he doesn't love his home- he does- but sometimes…

Sometimes.

Watching Mycroft watching it, though, he thinks, might be even more enjoyable. The boy is utterly still, utterly relaxed, more at peace then he has ever seen him.

Thunder booms close enough to shake the entire house. John jumps despite himself, and Mycroft's eyes snap open, wide and wild for one moment.

"Close." John murmurs, hand on his pounding heart.

"Loud." Mycroft mutters, seeming to wake from his stupor. He turns his gaze to John, tucking up more firmly and yawning. "You might want to go find Sherlock."

One the one hand, John feel the knot in his chest unravel just that much more. That Mycroft is unconcernedly informing him there might be a problem rather then racing off to go find his baby brother and hide from him shows just how far they've come since the Mary Incident.

On the other, concern makes it knot more tightly.

He stands, setting down his book. "Why?" He asks softly.

"He's not fond of storms. Or any loud noises, really." Mycroft has gone back to looking out the window. "He never has been."

"Where is he, Mycroft?"

"Probably in his bedroom. Probably under the bed." Mycroft at last turns to face him. "Normally I would be there, with him." He says, pointedly.

"I'll take care of him." John assures, gently. Mycroft studies him for a long moment, and then inclines his head slightly in a manner so adult that John is not sure if he should laugh or cry.

He stands, leaving the room- the last he sees of Mycroft the boy is tucking up again with a sleepy yawn and leaning on the arm of the chair- and goes to find Sherlock.

He finds him exactly where Mycroft has said; curled into a ball under the bed. And he has every time since.

At first, he thought it was just the storms, but after a few weeks he quickly realizes crowds, busy streets, public places, even average places that were common to visit. It wouldn't be long before the boy would be hiding pathetically behind John's leg or clamping his hands over his ears and chanting (in French, disturbingly, which John hadn't realized he'd known. Mycroft explained that they'd had a father who was multilingual. They both knew a little of a lot, but French they spoke nearly like natives.)

He tries everything he knows to help the boy; but frankly, outside of sedating the poor thing, there's very little one can do for heightened senses. Mycroft suffers from it, too, though to a much lesser extent, and seems much more able to handle it. Though, every once in a while, he will see Mycroft flinch at a particularly loud sound, or withdraw into himself when in the middle of a crowd; but frankly, the boy is wide and tall and only getting bigger as he gets older, and it's pretty impossible for him to simply disappear.

It's the day John ends up cradling him in his arms, rocking him gently while he whimpers and mutters and clamps his hands over his ears so hard he draws blood in his own scalp and Mycroft watches from the other chair, looking helpless and smaller then such a big boy should ever look, that John decides that enough it enough.

But he's still not sure what to do about it.

He figures it out by accident.

If John can get Sherlock to focus on one thing- just one thing- then he'll calm down. First it's simple; his voice. He holds Sherlock in his arms and rocks him and just talks, because he doesn't know what else to do, but slowly the boy relaxes and his hands move from his own head to John's shirt and his face hides there, too. And John realizes the more he talks the more Sherlock calms, and Mycroft has sat up, staring hard at both of them with that gaze far too old and too wise for a young boy.

So John keeps talking. A low, steady flow of words, nonsense words, meaningless, about the weather, a book, trips planned, patients, anything that happened to come to mind. Everything.

Ever since then, he knew what he had to do. Talking to him works best; Sherlock latches onto his voice like a drowning man to a rope. But sometimes he can get the young man to focus on a puzzle, or a certain thing or person, or get him talking, or working over some problem.

Years later- when Watson is aging well and Mycroft holds a government position that doesn't surprise him at all and Sherlock is becoming the most well known private- consulting- detective in London, perhaps even beyond it, definitely beyond it to a point- Sherlock shows up at his front door. He's pale and wane and when Watson ushers him in, the dark-haired man doesn't have to say a word. John just wraps Sherlock in his arms and lets him shake and shake, and talks quietly about the weather.