The day after the confrontation in the staff room, McGonagall paid Snape a visit at his home in Spinner's end where he was beginning his research into the possibilities for unexpected consequences tied to his vow.

After they exchanged polite greetings, McGonagall sat across from Snape looking grim. "I went with Dumbledore. It wasn't Harry."

"Of course it wasn't. Did you really expect otherwise?"

McGonagall sighed. "No, but it does not follow that I lacked hope."

That much Snape could understand. He had half hoped for it as well, wishing that he could begin to fulfill his vow to protect the boy. "Did he tell you whose information led to this particular excursion? Not that duplicitous Fletcher again, I trust?"

"Dedalus Diggle."

Snape rolled his eyes. "Diggle's as foolish as Fletcher is dishonest."

"Not as foolish as all that," McGonagall disagreed, then amended, "At least not this time. The boy in question had dark hair, green eyes, and a scar on his forehead. And not a spark of magic."

Snape glowered. "Tell me Dumbledore didn't abandon the child based on the belief that Harry Potter couldn't possibly be a squib." Leave it to Dumbledore to make the assumption that the child of prophecy could not possibly lack magic and thereby end up abandoning the boy he claimed to wish to rescue. Snape was on the point of demanding the location of the child in question so he could determine the truth for himself, but McGonagall's reply quelled the concern her earlier words had inspired.

"No, no! Of course not. It is most definitely not Harry. The scar, while jagged and shaped roughly like a bolt of lightning, was not a curse scar but one acquired by mundane means. A car crash, his parents informed us. And yes, they were his biological parents, not adoptive. Albus made certain that they were telling the truth and that their memories had not been altered."

Truth serum and legilimency, Snape surmised. Likely followed by obliviation. He did not envy the muggles the headaches they had undoubtedly woken up with this morning. He found himself pleased with the headmaster's thoroughness, however. Absently he wondered at the marked increase in protectiveness he was feeling towards the Potter boy. Was the change due to his resolution to defend the child, or had it been magically enhanced? One more question to add to his list.

"That is good, then," he said, realizing that he had been lost in his thoughts long enough for McGonagall to begin looking concerned. "Do you know if Dumbledore will continue the search after yesterday's incident? Or, rather, will he continue to keep you—and through you, me—informed of his efforts, for I doubt anything could cause him to cease searching."

"He will."

"You sound very certain."

McGonagall smiled a tight, calculating smile. "We spoke of the matter. He is not pleased with how things stand now, but he also recognizes the serious nature of the vow you made. I believe…that is Albus has given me good reason to believe that he will not oppose you and may even be of assistance."

"What precisely has he said?"

"You shall have to speak to him if you truly wish to know. He did say he intended to send an owl, though."

Snape picked up his wand and summoned a piece of parchment. "He requested we meet and 'discuss matters.' I did not reply."

"Perhaps you should. You might be surprised at what he has to say."

Snape closed his eyes for a moment, considering. He would have to speak to Dumbledore, he knew, and he could not put it off too long. But the emotions were still too fresh, too raw. "Not today, Minerva. I need more time. When you see him next, inform him that I will be in contact before the end of the summer holidays."

A disappointed look crossed McGonagall's face, but it was followed by understanding. "I will let him know. Don't wait too long. A wound left uncleaned may fester rather than heal. And now," she stood, shaking the wrinkles out of her robes, "I shall leave you to your thoughts and your research."

H~*~P

Although Snape had an extensive collection of books, there were very few relevant to his current search, his interests having focused more on potions and the dark arts. Within a few days he had exhausted that resource and had returned to Hogwarts to search through the library's restricted section with Flitwick. They spoke little, just enough to coordinate their efforts, and by the end of the week had amassed several yards worth of notes.

At the moment, Snape was perusing a book that had an entire section on spontaneous magical adoptions.

When a witch or wizard of age assumes the burden of care or protection for an otherwise unprotected magical child, their magic may effect an adoption as legal and more binding than any human ceremony. This is rare, however, as it may only occur when the following conditions are met:

The list that followed was short, but the first item certainly did not pertain to himself and the Potter child, and so he put the book to the side, making a note as he did so to eliminate adoption from the list of possible magical consequences. It was a shame, he thought, as the adoption would have been instantly reflected in any number of official documents, giving him the legal right to protect the boy as he saw fit.

"Erebus is very quiet today," Flitwick said, returning to his seat after retrieving a stack of books nearly as tall as himself.

"Indeed." Snape selected a new book from the pile and opened it.

"I rather expected he would cause a bit more fuss at being in the library for hours each day, but he has been very well behaved since our arrival. Nary a peep out of him, and none of his usual antics."

Based on the friendly tone, it was clear that Flitwick meant it as a compliment, however his words froze Snape to his chair and caused a cold sensation to grip his chest.

Birds often hide their illnesses.

Had not all the muggle books on parrot care he had acquired said that subtle changes in behavior, including sleeping more and vocalizing less, could be indicative of serious illness?

Shutting the book in front of him with a snap that would have drawn a glare from Madame Pince had she been present, Snape stood. "You will excuse me, there is an important matter I must attend to. I will return as soon as I am able." He directed a brief bow towards Flitwick in acknowledgement of the man's continued assistance before calling Erebus to him and striding out the door.

Five minutes later, after ascertaining that Silvanus Kettleburn was not in the castle, Snape's long legs were carrying him toward Hogsmede with as much haste as could be managed without breaking into a run. It took him twelve minutes to reach his destination. Twelve minutes fraught with unaccustomed worry. Not since he had realized the Dark Lord had targeted the Potters and their son—had targeted Lily—had Snape been so consumed with fear for another being. He had failed to save Lily; had his preoccupation with his research caused him to fail Erebus as well?

The magical creatures veterinarian, Panacur Theracens, a tall witch with a soothing voice and a kind face, ushered them into her office with a smile that Snape could not return.

"Aren't you a handsome fellow?" she said, after convincing Erebus to step off Snape's arm and onto a perch on the examining table. "What seems to be the trouble?"

"Erebus has been quiet lately, and less active. Not at all his usual trouble-making self."

"For how long?" she asked, waiving her wand in a complex little dance about the bird's head. Erebus, who under normal circumstances did not take well to magic being performed on him by strangers, did not react. Snape's mood soured further.

"A few days. Possibly longer." That was as close as he could come to admitting that he had not been paying proper attention to his familiar. Yes, the research he was engaged in was important, but that was no excuse.

His silent recriminations were interrupted by another question. "And has he been eating?"

"Yes." Snape paused, "That is…he has not eschewed food completely, but it is possible that he has been consuming less than usual."

Doctor Theracens, nodded. "That would be consistent with what I'm seeing. Beyond that and a touch of dehydration, I see nothing physically wrong with him. However, I have to admit that my experience with non-magical birds is mostly owls and the odd raven. Parrot physiology is similar, but not entirely familiar to me, and I know next to nothing about their normal behavior. I doubt my scan would have missed anything currently life-threatening, but I cannot be certain that there isn't something wrong that will become serious if left untreated."

Snape ran a hand through his hair, realizing how much that gesture betrayed his emotional state but unable to suppress it. "What do you suggest then?"

"You have two options. First is to wait and see if anything changes. Coax him to eat a bit more. If he has any particular favorites, offer those, or treats. Anything to keep him from losing too much weight. Then, if he gets worse, or hasn't improved within a week, bring him back here."

Wait to see if whatever was wrong became deathly serious? Not bloody likely. Snape sneered at the very idea. "And the second option?" he prompted.

Dr. Theracens, was unfazed by his acidic tone. "Find a specialist in parrot health and behavior. It'll likely have to be a muggle unless you want to go abroad, since parrots aren't common familiars in these parts. Muggle methods may be slower, but their diagnostic abilities have come quite a long ways recently, as I understand it. In some ways their techniques surpass our own. Once you have a diagnosis you can decide between using the muggle treatment or devising a magical one."

Snape questioned Dr. Theracens further, but there was, according to her, no viable third option. He left the office, heart heavy, carrying his subdued familiar on his arm. Was there really any benefit to be had by going to a muggle veterinarian? He had seen what muggle medicine had done, or rather had failed to do, for his mother, and was wary of relying on it now. Yet, if Dr. Theracens, felt it was the only reasonable option other than waiting, well he would not just sit by and hope that Erebus's condition would not worsen.

Decision made, he directed his steps to the Three Broomsticks to floo to London (Erebus disliked apparation). If he were to visit a muggle establishment, he would need to procure muggle funds.

Diagon Alley was as crowded as usual, and Snape was scowling fiercely by the time he walked into the cool of the marble chamber that was the Gringotts main hall.

"Good afternoon," he said, nodding with respect to the goblin behind the counter. "I should like to withdraw some funds and exchange them for muggle currency, if you would." Without needing to be prompted, he handed over his key for inspection.

The goblin, whose nameplate read Gornok, tapped the key on the desk and riffled through the documents that appeared there. "Very well" he said, "and will you be making the withdrawal from your primary vault or from the trust vault?"

Snape blinked. "My primary vault. However, you have reminded me of another matter. As I have only acquired the trust vault recently, I should like to procure a full accounting of the contents."

Gornok showed his teeth in what Snape took to be a kind of smile. "Of course. I shall have the documents waiting when you return."

Two wild, and thankfully uneventful, cart rides later, Snape returned to Gornok to exchange his galleons for pounds, and to collect the promised documents and Erebus—familiars not being allowed into the depths of Gringotts.

Curiosity overcoming him, Snape stepped to a corner of the hall and untied the roll of parchment he had been handed. He skimmed the heading of the document, and then read it a second time more closely. That was impossible. Unless…

He needed to return to Hogwarts at once. Snape promptly retied the cord securing the parchment and stuffed the document into an inner pocket of his robes. "My apologies, Erebus, but we need to apparate."

H~*~P

Flitwick had not been in the library when Snape returned, but that was all to the good, as it allowed him to retrieve the book he had been reading earlier and leave without being asked questions that he was as yet unprepared to answer. Book in hand, he retired to his quarters and promptly firecalled McGonagall Hall in Caithness.

"Minerva!" he called out into the empty hall that greeted him. Empty, that was, except for a tabby cat that on second glance was most definitely not his colleague. The cat in question, disturbed from its nap by Snape's shout, sneezed once before stalking away. McGonagall appeared scant seconds later, radiating concern.

"Severus! What's wrong?"

It was a reasonable assumption on her part that something was amiss, Snape conceded, given his well-known preference for written communication unless the matter was urgent. "I have discovered an…anomaly that I believe is related to what occurred the other day, and I would value your opinion. Do you have a few moments?"

Her eyes widened briefly. "Certainly. Would you care to step through, or shall I come to you?"

Snape considered this for a moment. It might be for the best to hold this conversation outside of Dumbledore's purview. On the other hand, he was confident in the wards surrounding his chambers and had no knowledge of the ones the McGonagalls had in place. The voice of one of McGonagall's extended family in another room decided the matter for him; this was a conversation that necessitated absolute privacy. "Please join me in my quarters at Hogwarts," he said, and at her nod, withdrew his head from the flames.

As soon as McGonagall stepped through the floo he sealed it behind her. He then prepared a pot of tea, handing her a glass prepared to her liking.

"I was reading this earlier today," he said, passing her the book he had retrieved from the library, open to the last page he had read. He indicated two lines in particular, "That should preclude the possibility of an adoption, do you not agree?"

"Indeed," she said, after a moment.

"Then how might you explain this?" he asked, this time handing over the roll of parchment from Gringotts.

She scanned the document. "Trustee?"

"And guardian," Snape said, pointing out the next line. "Yet the book states that the child in question must either approve the change in guardianship within two days or have an established bond of love and trust with the adult making the claim. I am quite certain that I do not have any such bond with any child of an age to be Harry Potter."

Erebus, who had until that point been dozing on his perch, flew to Snape's shoulder peering down at the documents under discussion. It was the most interest he had shown in anything for several days, and Snape felt a small measure of relief at the possibility that his familiar might not be ill after all.

He reached up to stroke Erebus's head as he continued, "What I would like to know is, if the boy is indeed lost, how could he have been informed of my claim in time to properly approve it?"

"You suspect someone of concealing Harry's whereabouts?"

Snape picked up his teacup to take a sip, almost wishing for something stronger. "How could I not? And yet reason tells me it cannot be so. Sprout and Flitwick are earnest in their desire to find the boy, with not a hint of deception about them, and neither is skilled enough at Occlumeny to conceal such a thing from me.

"As for yourself, until last week, I doubt if you would have hidden such a thing from Dumbledore." He raised his eyebrows in question and McGonagall nodded at this assessment of her likely behavior. "And given the headmaster's reaction during our confrontation, I cannot imagine he would tell the child himself. But who else could it have been?"

"Perhaps he confided in a member of the Order?" McGonagall suggested, but Snape could tell she did not really believe it.

Snape waved the hand that was still holding his teacup, dismissing the idea. "Dumbledore is not one to share his secrets or his frustrations."

There was silence for a few minutes as both professors became lost in their thoughts. After a while, Erebus walked down Snape's arm to his lap, butting his head into the man's arm. Rousing slightly, Snape scratched the parrot's head, running the wild and unruly crest feathers through his fingers. Unruly feathers, like a messy mop of hair that would never lie flat…he stared. Memories half-forgotten sprang to mind, snapping into place like the pieces of a puzzle.

The voices and phrases the bird had known…

The letters dropped on the head table which they thought had been returned to sender…

The cupboard! Merlin's knotty staff, he had dismissed that as sympathetic magic. Was it really possible that he had been so blind?

Erebus butted Snape's hand again, but when the man did not resume the caress, he began to preen himself.

"Minerva?" he said, keeping his eyes fixed on the parrot and speaking softly as one does when they do not wish to startle away a half-formed idea. "When exactly did Potter go missing?"

"May of '85," she answered without hesitation.

"May to September," he muttered. "Four months would be sufficient, I should think."

"Sufficient for what?"

Snape met her eyes and with careful deliberation tilted his chin down. "To travel to Hogwarts from Surrey."

"No!" she whispered. "You don't think…?"

Snape cut her off her with a half-raised hand. Then he leaned forward, tilting his head to better look at the parrot on his lap. "Harry?" he addressed it.

Erebus froze, then snapped his head around to meet Snape's gaze, his crest rising and lowering repeatedly with uncertainty.

"Merlin," he heard McGonagall swear under her breath.

He had missed it. They had all missed it. Snape could only hope that the child had suffered no irreparable harm from maintaining his animagus form for so long.

Snape extended his shaking hand toward's his familiar's—his ward's—head. Erebus—Harry!—welcomed the touch, leaning into his hand. With infinite care, Snape smoothed back the still bobbing crest feathers, closing his eyes in mingled remorse and relief. "Oh, Harry."