When Harry opened bleary eyes the next morning, it was to see Snape leaning back in the desk chair, a book propped open on his crossed knee, his black eyes rapidly scanning text.

Harry shook his head, his hair flying wildly as he tried to think past a fog of early-morning confusion. Something was wrong, something beyond the fact that Severus Snape would be in his bedroom at all, or that Harry would be at Privet Drive in October. Something else... why was Snape wearing Remus' clothes, which didn't even fit him?

The Potions Master glanced up as Harry shoved the covers aside and sat up. "Good morning."

It was Snape's voice... It took Harry only a second longer to put it together. "Your potion!" he accused.

Snape brushed a long strand of black hair away from his eyes. "No need to panic," he chided. "We're safe in here." Setting his book aside, he fished in a pocket for a small metal flask much like the one the false Mad Eye Moody had used. "I'll take more now, though. It does seem to make things... simpler."

Harry ignored that remark to focus on the one before. "We're safe, you said. So Aunt Petunia's still all right?"

"She's still alive."

Harry looked away as Snape sipped from the flask. He remembered the flavour of rotting cabbage, the awful nauseous feeling sliding down into his stomach as he'd drunk that same potion, then the wrench of the change, itself... But the potion didn't seem to bother Snape. Either the man was used to drinking horribly noxious substances, or his formulation had improved on more than mere duration.

It was Remus' familiar voice again that said, "I found this book downstairs. Read this part."

Harry took the proffered tome, Leukaemia: Diagnosis and Treatment, and ran his eyes over the paragraph Snape had pointed out. "I... I don't really understand this, Professor," he admitted when he'd read it through twice. Without even realizing he was doing it, Harry braced himself for a caustic comment.

"No doubt you don't. It's badly written," Snape succinctly replied. "Muggle publication, so what can you expect? Pity they can't even write to the level of the average Hufflepuff, but still, after wading my way through the extraneous verbiage, I gleaned a few useful things. Get up, we'll discuss them over breakfast."

Remembering all they had discussed in the kitchen the night before made Harry wary. And resentful. But he didn't know how to broach that, so the resentment spilled out in another direction. "Are you going to let me make breakfast," he sniped, "or will it be another pizza?"

"If you'd seen your face, whiter than Mr Malfoy's as you stumbled off the lawn, you wouldn't have tried to stay on your feet. But you look fine, now, so by all means play the house-elf if you like."

"I don't like, but food doesn't just make itself, not here."

"Pity," Snape replied.

Harry shuffled through the bedclothes for his shoes and socks. Funny, he didn't remember taking them off. Must have kicked them off in the night... except that they were laid out neatly on the floor, socks folded, laces tucked away inside the gaping shoes. Irritated, Harry shot Snape a nasty glance. "Don't touch me, all right? Especially not when I'm asleep."

"You were thrashing," Snape explained, "and it looked all too likely that those huge... things would fly off your feet and hit something. What was in your dream?"

"Nothing."

"The Dark Lord? Death Eaters?"

"Nothing!"

"Cedric? Crouch?" Snape drew in a breath. "Black, Harry?"

"Aunt Petunia and Dudley, if you must know!" He rapidly pulled on his shoes and socks, and without another word, stomped out the door, down the hall and stairs, and into the kitchen. There wasn't much to eat, really, and the milk in the fridge had gone sour. Harry found some tinned milk and dry cereal --god awful sugary stuff that Dudley had demanded ages ago-- and had a simple breakfast on the table in under three minutes.

Snape didn't comment on the cuisine, though he didn't eat much, either. Harry had three helpings, washed down with some orange juice he'd mixed up from frozen, and afterwards, he felt a lot less grouchy.

"All right, let's have it. What did you find out from that book?"

"You're in the range of relatives who might be bone marrow compatible."

Harry scratched his head. "Yeah, all right, I guess that makes sense. Uncle Vernon said he and Dudley had tried to donate, and been refused. You think I could donate, then?"

"It's within the realm of possibility," Snape answered. "And this book is well-thumbed; I'm sure your uncle knows that you should be tested, at least. But he didn't mention that. All he asked for was your magic."

"Weird," Harry had to say. He poured himself another glass of juice. "It's not like he's come around to thinking that magic is all right, so why wouldn't he rather have my marrow than... oh, so that's it."

"Come again?"

Harry flashed the sort of grim smile that always accompanied epiphanies about his relatives' regard for him. "Bet you anything they think my bone marrow would taint her, or something. You know, with magic."

"Interesting notion," Snape murmured. "Wizard blood is in fact a highly magical substance, and Muggle theory insists that blood cells themselves are born in the marrow. Though that may not hold true for us, you understand. Still..."

Harry laughed. "Oh, please. Petunia as a witch." Suddenly it wasn't funny, not at all. "You know, I think she would rather die. No wonder they didn't ask me to donate. The way they figure it, magic to heal her would be safer. Controlled. Though it's anybody's guess why Uncle Vernon would associate magical control with me. He's never seen me do a real spell, just... accidental magic."

"All wizard children do that," Snape lightly observed. "It only means that you are in fact normal."

"For a wizard."

"Yes. For a wizard."

Harry piled the dishes in the sink, then turned back towards the table where Snape still sat. "So, what do we do about Aunt Petunia, then?"

"It's your choice," Snape replied, fingers tapping on mahogany. "You can pretend to do some sort of spell, and hope they believe it worked. I could even place a glamour over your aunt to make matters look authentic, though that wouldn't change her true state of health."

"Can you glamour the machines, too?" Harry pressed. "There's one for blood pressure, I think, and they probably track her temperature. And... well, I don't know what else, but you could just make all the equipment show normal readings."

"I wouldn't know what constitutes normal for a Muggle," Snape pointed out. "Although research could remedy that problem. Still, magic is highly organic. It's wedded to the natural world, to be  used by living beings for living beings. Altering complex machines with it could have... unforeseen consequences."

Harry remembered Hermione's many lectures on how Muggle technology didn't even work in the presence of excess magic. "Yeah, better scratch that idea," Harry conceded. "Okay, so we can fake a spell, but not very well. Well, Uncle Vernon's like you; he doesn't trust me farther than he can throw me, either--"

Snape sat up straighter. "What did you just say?"

"I think you heard me." Leaning on a counter, Harry reiterated, "You actually are a lot like Vernon Dursley, you know. You both enjoy cutting people down to size, especially relatively helpless people, like students who can't fight back. You both just love to threaten people and watch them squirm. And it's more than threats, too. One after another yesterday, you both grabbed my arm and held onto it until it pleased you to let go, no matter what I had to say about it."

"I was keeping you from falling, you stupid boy!"

"I'd rather fall than be manhandled. Just like I'd rather sleep in my shoes if I want! If I need help, I'll ask, all right?"

Snape shoved back his chair so hard it clattered to its side on the linoleum. "That's just the problem, you don't ask!"

"Yeah, well I sure as shite asked for help with Sirius, didn't I? And all you did was look down your supercilious nose at me and tell me to sod off, because you wanted him dead! You knew he was blameless in my parents' deaths, but he wasn't innocent, not in your books, and you couldn't look past the fact that twelve years in Azkaban was punishment enough for-- for--" Harry abruptly stopped talking, because it was either shut up or burst into tears. Turning away slightly, he blinked to dispel the feeling.

"All right," he finally said when he felt more in control, though he didn't actually know if Snape was still in the room. It felt almost as though he had lost a span of time, as though he hadn't been conscious of anything for a few minutes. What had happened to his resolve to be mature? Sirius was dead, and Snape was glad about it, and no amount of blubbering would change a thing. Harry's hands had been gripping the counter until he felt like his bones would snap, but then he deliberately let go, and tried to wall his anger. "All right, so it seems like pretending to spell her is out. If the price of the wards is returning her to health, that leaves me donating bone marrow, I think. What else is there?"

"Is that rhetorical, or are you asking for help?" Snape stiffly replied.

Feeling suddenly drained, Harry moved toward a chair and waved for Snape to sit down, too. "I'm asking what you know, what you got from the book."

Snape didn't sit down, but he did answer, pacing back and forth as he reasoned, talking his way through the problem. Harry just watched and listened, his eyebrows drawn together in a frown. It didn't sound like bone marrow donation was a big deal for Muggles, but Snape was all too aware that Harry was a wizard, and an unusually powerful one, at that. Was Harry aware, he asked --without waiting for an answer-- that fewer than half of fully-trained wizards could produce any Patronus at all, let alone a corporeal one? And Harry had done it at the absurdly young age of thirteen. Preposterous, really, but Snape reasoned aloud that it shouldn't have surprised him overly much, given that Harry's own father had developed Animagus powers, without any training, while still at school.

It was well known, Snape continued after a short pause, that wizards and Muggle medicine didn't mix well, and the effect tended to be magnified for more powerful wizards, though very little was really known about the phenomenon; most wizards had enough sense to call a healer when they were ill. Still, children, the younger the better, were thought to tolerate Muggle interference better than adults, though this again was based on the occasional anecdote, which was hardly a basis for belief. And then there was the whole issue of wizard blood itself carrying the magical signature of an individual. It might make Petunia worse instead of better, especially as she had a strong aversion to magic in general and Harry in particular. On the other hand, Snape reasoned, it could instead serve as a catalyst to change Petunia's own core. Her sister Lily had been a powerful witch even when Snape had known her at school, and then later she had actually managed to save her child from the Dark Lord, so there had to be highly significant wizarding bloodlines in the Evans family tree, even if they'd lain dormant for long enough that the family had forgotten all about it... and on and on it went, Snape pacing and talking the matter through.

"You've given this a lot of thought," Harry had to admit when Snape finally did stop. "But if they only agree to help me because I'm going to give them marrow, isn't that a lot like bribery, anyway? You said that wouldn't work."

"I don't think Galleons can generate true good will," Snape corrected. "This could, if you're willing."

"If I'm willing?" Harry echoed. "What do you mean? What happened to you're going to get on your knees and beg even if I have to make you?"

Snape had the grace to look a little chagrined, at least. "I thought you were an ungrateful child who took your relatives' love and care so much for granted that you couldn't bother to even read their letter. James was a bit like that. He tended to put fun with his friends above family."

Harry thought about that, realizing with dismay that it did fit what he'd seen of his father as a fifteen-year old. "I wish people would stop confusing me with James," he murmured. "Well, I suppose there's not much choice to be made, is there? I'll have to donate my marrow. I don't see another way of generating enough good will."

Snape sat down across from him and splayed his hands on the table. "I think, perhaps, your only real choice is to leave your aunt to her fate. If we lose you in an effort to maintain the wards, we have lost all that matters. You've heard the prophecy."

"Lose me?"

"To Muggle medicine!" Snape hissed, scowling. "Weren't you listening? You are not a Muggle, Harry. You should not subject yourself to doctors, full stop. I should likely not have even mentioned it."

"So why did you?" Harry asked, head tilted curiously to the side.

"Because you are not fifteen and not an idiot," Snape sharply retorted. "You do better with more information rather than less, a notion the headmaster is beginning to appreciate as well, though I'm sure you don't believe that. You can weigh these matters for yourself. I said it was your choice, did I not?"

"Yeah," Harry mused. "I do know what you mean about Muggle medicine. Mr Weasley tried some stitches last year; they didn't work out so well. Of course, that might have just been because of the venom. But you know, I was Muggle-raised, which might give me an edge, and you said children could tolerate things better. See, I was listening. Although I sort of remember something strange about doctors, hmm..."

Snape eyed him critically. "What?"

It took Harry a minute for the memory to come clear, and even then he wasn't sure he wanted to reveal it. But after what Snape had just said about sharing information, he thought he'd better. "Well, I can remember going to the doctor lots of times, but mostly it was just for Dudley. One time, though... I don't know, I must have been three, maybe. Dudley was getting shots, and the doctor said that I was supposed to, too." At Snape's blank look, he explained, "Um, that's where they stick this needle in you so they can inject a... um, I guess it's sort of like a potion?"

Snape was barely breathing, Harry noticed, but he had air enough left in his lungs to say, "Was this done to you, Harry? This..." he sounded thoroughly revolted. "This injection of potion?"

"Yeah," Harry admitted. "But they had a time of it. When the nurse showed me the needle I screamed. I mean, really screamed. They had to hold me down, but when it touched my skin I felt this strange shivery wave sort of coursing through me. I... uh, made the needle bend double, I think. I'm not sure. I just know that Aunt Petunia started screaming, too, and then she hissed at them to get another one, and that time she held her hand over my eyes when they did it."

"I imagine you were punished," Snape surmised.

Harry shrugged it off, his mind so lost in the past that he'd forgotten, really, who he was talking with. "Whatever they injected, I had a reaction. I can't really remember the details. Just getting sick, so sick, and it was hot and sweaty in the cupboard, and I wanted to rinse my mouth, but they wouldn't let me out." The memory was one of his most chilling, probably because at the time he'd been too young to understand why nobody would help him. Harry shrugged again, and tried to leave it in the past. "Anyway, I never had to get another shot. I don't know how they got out of it, come to think of it. I have this idea that I should have had more, to be allowed to attend school." He gave a mirthless laugh.

"You were locked in that cupboard whenever you did accidental magic?"

"Oh, no, I lived in there all the time," Harry explained, then could have cursed his Gryffindor forthrightness. He should have just let Snape believe the other thing; it would have explained the black energy just as well. Some part of him, though, was relieved to let go of the secret. Yeah, the confused part of my mind that almost thinks he's Remus, he caustically told himself. Then he realised that wasn't really true. Or fair. Maybe it's the part of me that remembers yesterday. He tried to make the Disapparating easier, he made me sit down and rest instead of cook, he sat up all night to be sure I'd stay safe. He researched the leukaemia, and without even pointing out that I should have had the brains to think of that on my own.

"Harry?" Snape questioned, and somehow, the name clinched it.

"You aren't going to tell anyone," Harry murmured, but it wasn't a question, or a command.

Snape's gaze was level, almost non-committal; he didn't give any reaction at all, though he did say, "You aren't the only one with a sense of... decorum, about such things."

Harry supposed that was Snape's way of saying he'd understood that Harry had needed to talk to Sirius. Or maybe he was trying to thank Harry for not spreading Snape's worst memory all through Gryffindor Tower. A little of both, Harry decided.

"Yeah. Decorum, good word."

They sat in silence for a few minutes, until Snape prompted, "So. It is your choice, Harry. We can go back to Hogwarts without further comment and never speak of this again. No doubt your aunt will die, and the wards will fall, long before summer comes, which will free you from the necessity of ever coming here again."

"Talk about tempting," Harry admitted. "But you're the one who said Hogwarts wasn't completely safe. And how could it be, when Dumbledore's idea of a Defence teacher is a bloke with Voldemort sticking out the back of his head? Much as I hate it here, I probably do need to hang onto the one place on earth that might actually keep me secure. And if that means Muggle medicine gets its hands on me?" He lifted his shoulders.

"Hogwarts may be a safer option than subjecting yourself to the marrow extraction procedure," the professor pointed out. "From your account, you were highly averse to Muggle medicine even as a child. And now you're nearly full-grown, and the medicine in question is far, far more invasive. Accio book," he suddenly called, waving his wand toward the upstairs bedroom.

After the book landed on the table with a thud, Snape flicked his wand to make the pages turn themselves at high speed. He muttered an incantation at the flipping pages, some series of Latin phrases Harry had never heard before. The book abruptly went still, and Snape flipped it around to face Harry. "Read this chapter before you decide," he instructed.

So Harry did, pulling awful faces all the while.

---------------------------------------------------------------------

"Oh, ick," was about all he could say when he first finished reading. "That was completely gross from start to finish. And they use needles. Just what I need."

"You can see why I have reservations."

"Yeah," Harry admitted. He did wish he could run away home to Hogwarts, but he knew the wish was selfish, on several fronts. "Um, but it doesn't really matter, you know? I mean, I'd have to do it even if I wasn't angling for the wards. She is my aunt."

"You do know how irrational that sounds?" Snape returned, shaking his head. "She may share your blood, but she's been your aunt in name only, Harry. You do not owe her a thing."

"I owe my mum," Harry clarified. "She wouldn't want me to let Petunia die, not when I might be able to forestall it."

"You might be surprised," Snape tightly informed him, eyes fierce. "I knew Lily Evans. I heard her talk about her magic-hating Muggle sister. That alone should have told me that my assumptions about your first eleven years were erroneous. At any rate, I have no doubt that your mother would not want you to undergo a painful, highly dangerous and dubious procedure in hopes of saving someone who has treated you so shamefully."

Harry didn't know what to say to that, since the Potions Master did have a point.

"Furthermore," his teacher went on, "your mother gave her own life to save yours! Do you think she would want you throwing that away for the likes of Petunia Dursley?"

"A little dramatic, as scenarios go," Harry shot back. "Get a grip, would you? I'm not going to die!"

"How do you know that? Have your Divination skills improved?" Snape sneered, waving his hands in a random manner Harry'd never seen from him before. "I did see your O.W.L. results, Mr Potter!"

"Look, if I can survive Cruciatus, I can put up with a needle shoved through to bone."

"Cruciatus," Snape gasped, his hands falling gracelessly to the table, so hard it would leave bruises. "What do you mean, Cruciatus?"

"Aren't as well-informed as you think, are you?" Harry sneered. "Yeah, you heard me. Voldemort cast it on me after he snatched me from the Tri-Wizard Tournament. Imperio, too, and I still made it out of there alive. I'm pretty adaptable; if I wasn't, the Basilisk would have got me! So just stuff your worries in a sock or something--"

Harry abruptly shut up, his mind clanging on a single thought. Oh, shite. That's it, that's why he's looking so shattered, why he can't meet my eyes. He's worried about me. Not the prophecy, not the future... me.

"It'll be all right, you'll see," Harry resumed in a lighter tone. "Trelawney would no doubt predict my demise, but she's been wrong every time yet, so you don't have to... er, be concerned."

"Cruciatus at fourteen. Dear Merlin." Snape's fingers curled into claws. "Haven't you endured enough? Why must you do this, too? Don't excuse it on account of your mother. I guarantee she would not want this."

"Well," Harry murmured thoughtfully, glancing sideways at Snape, "Hermione would say it's because I have a saving-people thing."

"That is singularly not funny, Mr Potter."

"Better switch back to Harry; I want to go out."

"Out?" Snape looked like he was still contemplating the curses Harry had endured.

"Yeah, can we? You don't sense any dark magic outside, do you? We should head to the hospital, I guess, but I really don't want to Disapparate if it can be avoided."

Snape nodded, pointing his wand, revolving it in a slow sphere, even pointing it towards the floor and ceiling at times, as he incanted Finite Incantatem. Then he swept the wand in a wide arc, his eyes blazing with concentration. When he finished, he shook his head in dismay.

"I think perhaps you'd better come here, Harry."

Understanding what the professor hadn't said, Harry stepped close. Remembering the last time, he closed his eyes and stayed still, only flinching slightly when Snape laid an arm across his shoulders. Then the world was melting around them and through them, but at least when Harry realised he was in the hallway just outside Ward 328, he was still on his feet.

Swaying, almost incoherent, his stomach somewhere near his knees, but he was on his feet.

He took a moment to breathe deeply, some vague part of him glad to still have that arm around his shoulders. Even better, when he went to shake it off, it moved away at once.

"All right?" Snape asked, but not in a pitying way. Just matter-of-fact. Harry liked that.

"Yeah, fine. Winded, but fine. Er, thanks."

Snape gave a slight gesture as though to brush that aside. "Are you sure you want to do this?"

Harry grimaced, but nodded. How bad could it be? Not worse than that dunce Lockhart removing his bones and Madam Pomfrey having to regrow them, surely. Certainly, it couldn't be any worse than Cruciatus, even if he didn't respond to the procedure the way a Muggle would.

An audible breath escaping his lips, Snape remarked, "I must admit, I find myself hoping that you won't be considered compatible, Harry."

"Ha. With my luck?"

"Perhaps your family will refuse, on account of..."

"My abnormality," Harry finished. "Well, there is that. I may just have to insist."

Snape placed a hand on his shoulder when Harry tried to go in. "Miss Granger may be right, you know."

"About my saving-people thing?" Harry sighed. "Well, let me just get to it, then."