A/N: I owe a huge, huge debt to Pygmymeese, without who(m) this would never have existed beyond a vague outline in an email I sent her about a month ago. She also beta'd this not once, but twice, despite this being the busiest month of her year. She has been wonderfully patient with my tendency to decide that I need to rework the entire thing, several times. Thank you so very much.

Disclaimer: I don't own it, I never have owned it, and I never will own it. If I did, it would be much angstier, and Alex would have enough psychological conditions to fill a text book.

Kay has been going out with Ben for about six months now, and she's pretty sure that it's serious. She's met his parents, his brother, and even his friends, although they all watched their words around her for some reason.

So when he phones her up one day and asks her if she'd like to go out that evening, there's nothing new about it. What is new is the hint of nervousness in his voice and bearing when he picks her up from her flat. She waits until they are in the car to ask about it – that way he can't deflect the questions.

"What's going on, Ben? Where are we going?"

Ben doesn't look away from the road, but his face is serious when he answers her.

"There's someone that I'd like you to meet."

By this time they are driving through the outskirts of London: quiet, leafy suburbs with houses set back from the street, and estate cars in every drive. It's obviously an affluent area.

Ben pulls into the driveway of one such house. Kay hears him take a deep breath before he opens the car door. She's nervous now, and a little worried. This seems to be a big deal for Ben, but he still hasn't told her where they are going. Ben swings the gate open for her – always the gentleman - and they walk down the mosaic path and climb the steps to the front door. Their shadows are black against the bright painted wood. Ben knocks.

The door is opened by a pretty red-head who is laughing and calling something over her shoulder. Kay isn't sure what to make of her: should she be jealous? (The woman really is quite pretty.) Or perhaps a little wary? (Ben still hasn't told her anything.) Or maybe both? Or neither? Or -

"Ben, hi! Alex didn't tell me you'd be over tonight."

"Hi, Jack. Is he around? I heard he got back yesterday."

"Yeah, he's upstairs. I'm so sorry, where are my manners? Do come in." The redhe- Jack- steps out of the threshold, allowing them into the hall. Kay glances around. It's really a nice house– all high ceilings, tasteful pictures, and polished wooden floors. Kay can see a fire alight through a door that is slightly ajar. She finally decides she is envious, intimidated, but mostly confused.

"Kay, this is Jack. Jack, my girlfriend, Kay," Ben introduces them. Jack laughs.

"Now your unexplained visit makes a whole lot more sense than it did five minutes ago. Pleased to meet you, Kay." She holds out her hand, no trace of animosity in her face.

"Um, it's nice to meet you too," Kay replies, still a little confused. She's clearly not here to meet Jack.

There's a creak from the stairwell. Kay turns to look. At the top of the stairs, a boy has appeared. He's muffling a yawn and squinting his eyes against the light. His fair hair is a mess, there are pillow creases on his face, and his tracksuit bottoms hang low on his hips. He looks nothing like Jack. Or Ben, which was Kay's other theory.

"Who is it, Jack?"

Jack opens her mouth to speak, but Ben stops her with a familiar hand on her arm. A smirk is firmly in place on his face. Kay has never seen him smirk just like that before, although it looks similar to the one Kay uses when her brother has done something rather stupid and hasn't realised it yet.

"Have you just woken up, Alex? I seriously wish I had a camera. I could put the picture on Wolf's mantelpiece when his mother comes to stay. It'd be a great laugh."

Alex's eyes fly open and he scowls, slipping step by step down the stairs.

"Wolf doesn't have a mantelpiece, Ben. And anyway, you wouldn't dare. 'Cause if you did, firstly, Wolf would make your life very painful, and secondly, do you remember that time that you forgot the video camera was running? I'll send those stills to your mum, and she'd frame them and put them on her mantelpiece." he retorts quietly.

Kay can tell they have been round this block before. She follows them into the lounge, and Ben takes a deep breath and introduces them. Alex raises an eyebrow for a moment, and then nods at her. He makes no motion to shake her hand or touch her in any way, but Kay can feel Ben tense behind her, so she just nods back, awkwardly. So this quiet, strange child is the person whom I have been brought to meet. On the surface, it seems so inconsequential, but Kay isn't stupid. This is big. Actually, it feels bigger than when Kay met Ben's mum, if that's possible - Kay decides firmly that she will never, ever, tell that to Mrs Daniels.

Kay and Ben sit on the sofa as Alex curls up in an armchair across the room. His posture is clearly tense and strangely defensive. Jack shoots Alex a worried look before going into the kitchen to make dinner. Ben is the one that talks, for the most part, relating funny anecdotes that have happened since the last time he saw Alex (most are new to Kay as well), and discussing news from mutual friends, people whom Kay has never heard of before. Some guy named Wolf – a rather ...unusual nickname (at least, Kay hopes it's a nickname) - seems to crop up a lot. For the first twenty minutes, Ben chats with Alex, trying to bring him out of his shell, and although Alex answers quietly and monosyllabically, Kay can feel his eyes and his attention on her, watching and assessing. It's like being stripped of all of her secrets.

"So, where did you guys meet?" Alex's voice is barely more than a hoarse, painful whisper, but the question is addressed to Kay. Ben stops talking abruptly and smiles a slow, small smile, as if he cannot contain it. It looks a lot like relief. There is a code here that Kay can't translate, or has missed in some way.

She tells Alex how Ben was behind her in the queue when she volunteered to do the coffee run for her colleagues and how, in her haste, she managed to spill six cups of coffee and a blueberry scone all over him. Ben winces at what must be a rather embarrassing memory, but keeps his mouth shut.

After she's finished the anecdote, Alex is smiling cautiously and Kay ventures a tentative question about his schooling; before she knows it, they are chatting. Alex uncurls a little from his chair. Beside her, Ben's tension eases a little more every time Alex's lips twitch into his tentative smile.

Kay watches Alex as they talk. He looks so young, sat in that chair, hair still messy from sleep. His skin has no colour in it at all, like a porcelain doll: fragile, as if the slightest knock would break him in half. At the same time, there is something, his air, mannerisms, that contradict his physical frailty and his defensive body language. He's an enigma.

"So, how do you two know each other?" she asks.

It's clearly the wrong question. There is a sharp intake of breath from Ben, and Alex tenses, the little relaxation he's gained immediately lost. She doesn't take it back, though, and Ben eventually fields it, when neither Alex nor Kay makes a move to end the uneasy silence.

"Work experience. Alex shadowed me for a couple of weeks about two, maybe three years ago, and we kept in contact after he left. He's the best work experience student we've ever had."

Alex relaxes a little.

"Yeah, and those were two weeks of hell, I don't care how many records I broke. They were probably nothing compared to dealing with four year olds every day. Tell me more about what you do, Kay. You said you were a primary school teacher? How did you get into that?" Kay talks about her job (which is great) and lets them skilfully turn the subject away from dangerous ground. Let it be- for now.

During dinner, Alex is mostly silent, and looks progressively more exhausted the later it gets. Jack and Ben keep up the conversation and the food is delicious, but Kay is too busy thinking to be more than polite.

Kay has known Ben for just over six months now, and he has carefully avoided any questions she has about what he does. All he's told her is that he works for the government. She knows that it pays well: he lives in an upmarket area of town and drives an expensive car. She knows it's important, the late hours, unexpected absences and his polite insistence on taking calls at inconvenient times prove that. Her only clue to this mystery of Ben's is Alex, who is as much of a mystery as Ben himself. Alex, who hasn't spoken above a whisper all evening, who is drinking deeply from a glass filled with something horrifyingly unidentifiable, leaving the food on his plate untouched. What kind of child takes three different types of tablet after his food without complaint? Who is Alex, and why is he so important to Ben?

Afterwards, Ben and Kay make motions to leave fairly quickly; Alex's exhaustion is apparent to all.

Just before they go out of the door, Ben hesitates.

"I'll meet you in the car, Kay. I just need to say goodbye to Alex."

Kay doesn't mention that he already has.

After Kay has gone out to the car with Jack, Ben turns to Alex.

"What do you think?"

Alex shrugs. "Nice. She been checked?"

"Yeah, twice. How's the meds?"

Alex grimaces. "I'm not sure which are worse, the tablets or the toxins."

Ben wrinkles his nose in sympathy. "Are you still sleeping a lot?"

"Yup."

"And your voice?"

"Painful, but at least it's back. Could've been worse."

"Yeah, you could have lost it altogether. Remember, you're not allowed to leave the house, or it'll go again."

Alex rolls his eyes and shrugs. The unsaid 'Stop fussing, I'm fine.' hangs in the air between them. Ben changes the subject.

"Looking forward to proper food again?"

Alex nods. "That mush stuff I have to drink is horrible, but it means I can go back to school in about a month instead of three, so I'm drinking it."

Ben feels his heart break for his 'little brother'. He's good at hiding it though. Alex is only at home to pity when he is at his very weakest, and even then, his tolerance is pretty low.

"Right, well, I'll let you crash, but I'll be over about lunchtime tomorrow. We can talk debriefings then."

They hug, and Alex lets Ben carry his weight for a moment as his knees buckle, (so much less than it should be – perhaps that toxin cost Alex more than he's told Ben). When Alex is steady on his feet again, Ben carefully lets him go.

"You gave me and Jack quite a scare this time, Alex. Less reckless next time, eh?."

Alex nods again, but Ben knows he won't be. Alex's most dangerous enemy is his own sense of honour, his own luck. It makes him seem invincible, especially to himself. One day, it will desert him when Alex needs it most. Fleetingly, Ben feels helpless.

He pushes his fears aside, and goes to open the door, turning when Alex calls to him in a soft voice. Alex has a steadying hand on a chair and his face appears grey in the dim light. He looks so young.

"Ben."

"Yeah?"

"She's good for you."

Ben opens the door as a grin splits his face in two.

I hope you enjoyed it! There should be more from Kay at some point, if you're interested in hearing more from her. Thank you to everyone who took the time to review 'The Nature of Friendship'. It meant a lot.

Sequel: Small Steps