Disclaimer: I own a copy of all the books, but not the franchise and/or copyright.
Severus Snape gently positioned the baby in his arms into a standing position on his lap. Said baby—a healthy 18-month-old boy, to be exact—beamed up at him and bent his knees, then straightened up abruptly. As the baby had secretly hoped, Snape lifted him up into the air as his knees straightened out fully, giving the baby the feeling of jumping into zero gravity.
"Never get tired of this game, do you Harry?"
And then, as Snape lifted him again—"Taaaa!" Pure delight.
Harry Potter, recently orphaned by Voldemort, and Severus Snape, not quite Death Eater. It was an unlikely combination. After all, while Snape wasn't a Death Eater, it was suspected that he was one of few potions makers willing to make potions for the Dark Lord.
Of course, when you took into account that he and Lily Potter, nee Evans, had grown up together and were rather close friends, even after Lily's marriage, the fact that he now had custody of little Harry made a bit more sense.
He had, after all, been appointed the position in the Potters' will, if Sirius Black wasn't able to take the child. And considering the fact that Black was currently taking a permanent vacation in Azkaban Prison, it made perfect sense that the one to raise the boy with the shocking title of "boy-who-lived" would be Severus Snape.
Unless, of course, your name happened to be Albus Dumbledore. Then you would be too concerned with silly things like warding and keeping a one-and-a-half-year-old's head from getting too big.
So, Snape and baby Harry were currently relaxing in a hotel room somewhere in Japan. They had been moving around Europe and Asia, for the most part trying not to stay in one place for longer than a few weeks. Snape figured that eventually Dumbledore and the Ministry would get tired of looking and would presume them both dead. Until then, they would keep moving.
"You know, Harry, I don't want to rush you or anything, but you're nearly two years old."
"It would be pretty nice if you could say a word or two. Not to depreciate the value of 'ta', but it's not technically a real word. I mean, I know I'm not 'mama' or 'dada', and I know you know that. You're a smart boy."
"But you could say some other words. Like 'bed', or 'doggie', or 'strange man who plays with me'. Anything like that, you know."
Harry was, in fact, a smart boy. He was aware of lots of things. He knew that his mama and dada were gone, and that the man he stayed with now was neither of them. He knew that he wasn't at home anymore, and that they traveled a lot.
In his reasoning, the only word he had ever spoken that still applied to his situation was 'ta'. It conveyed whatever he wanted to say. And until he figured this new situation out, and was around this new person enough to hear other people talk to him and say his name, he would just stick to his own word.
"Well?" asked Snape hopefully.
Snape sighed. Well, some kids just didn't talk until they were three or four. It happened sometimes, and little Harry had certainly been through enough trauma to suppress his development. He supposed he should just be happy the little guy was a happy baby.
FOUR YEARS LATER
Severus Snape and Harry Potter stood hand-in-hand in a darkened room. They were in an aquarium in a city in a country where people spoke a language Snape didn't know.
Jellyfish were in the tank the two were gazing into, flowing and florescent and absolutely stunning. Five-and-a-half year old Harry brushed across the glass with his free hand, tracing a jellyfish's long stingers. "Ta…" he murmered breathlessly.
"Ta indeed." Snape agreed quietly, awed by the fantastic display. He had figured the aquarium would make for a good science lesson, but now he supposed that it made for just as good a lesson in art.
He had begun teaching Harry basic math and reading, and while the little guy would gladly do arithmetic and write his letters on paper, he refused to write or speak actual words. Just 'ta', for anything and everything. Snape had begun reassuring himself with the fact that Einstein hadn't spoken until the age of six.
Of course, Harry was rapidly approaching his sixth year, and still showed no signs of being willing to talk.
Harry himself, on the other hand, was both free of concerns and perfectly content. He had decided that he would be just fine with his one word. He had experienced a lot of different languages in his short life, and wasn't content to use just one of them. So he continued to use 'ta' for his everyday needs.
He was also being conveniently ignorant of Snape's light concern over his development.
After a few more enchanting moments of watching jellyfish dance about, Harry tugged on Snape's hand and moved towards the next room.
"Coming, coming. Calm down."
Snape knew Harry was a bright boy. And if he never spoke, Snape decided it would still be alright.
SIX YEARS AND SEVERAL MONTHS LATER
A nondescript barn owl swooped through the window of a small apartment in an equally nondescript building in a city in Canada. It landed on a small kitchen table and offered its leg to the little boy sitting at it. Ten-year-old Harry Potter untied the letter attached to the proffered leg, and the owl took off again.
As if by magic, Severus Snape appeared behind him. "Open it." he suggested quietly.
Harry did, then read it, then gave a mildly surprised "Ta!"
Snape already had his wand out and was packing their meager belongings. Now that the Hogwarts letter had been successfully delivered, Dumbledore would not only know that Harry was still alive, but would know where they were staying. They would have to move again.
Harry took the full backpack Snape held out to him and waved the open letter towards him. "Ta?"
"Yes, we should probably burn it. Give it here."
Snape cast a quick incendio, then ushered Harry out of the apartment. Even if Snape might have considered trying to let Harry attend Hogwarts, he had heard rumor that whispers of Voldemort were beginning to be heard in England. Snape didn't want Harry anywhere near there if that rumor turned out to be true.
Besides, it would be awkward for Harry to try and fit in at a school when his vocabulary still didn't go beyond one word. Snape was pretty sure he could teach Harry magic himself. It wasn't uncommon for insular families to home school their children in lieu of sending them to a magical school, anyway.
"Stick close now, we're going to apparate to a floo point."
Harry gave an affirming nod and nestled himself into Snape's side. "Taa."
The two of them disappeared with a pop that went unnoticed by the empty street.
EIGHT YEARS LATER
Severus Snape took a sip of coffee and gratefully accepted the morning newspaper from the waiter at a café in Italy. One spell later, he was reading the latest wizarding news from around the globe in English.
Exactly three minutes and fourteen seconds later, he dropped his coffee cup, threw a handful of euros onto the table and took off at a frantic pace, aiming for the apartment he and Harry Potter had been sharing for the past four months.
The reason for his haste was the amazing news held in the paper—after Voldemort's sudden reappearance in England, and subsequent takeover of the Ministry of Magic, Voldemort officially apologized to the other nations of Europe for the inconvenience the fighting in England might have caused and shipped all the foreign prisoners that had been being held in Azkaban and ministry holding cells back to their home countries.
Voldemort had gotten what he wanted and had no intentions of taking over more than his little home country.
Snape resisted the urge to give a whoop of joy and practically ran the rest of the way to his and Harry's small apartment.
"Harry," he gasped out upon his arrival, "you won't believe what's in the news today."
"Voldemort has finished his takeover of England and isn't interested in any other countries. We don't have to worry about him or the ministry anymore!"
"Ta!" Harry looked delighted at this news. He hadn't lived in the same place for more than a few months since he was a year old. Voldemort's non-interest in the rest of the world in general meant that he and Snape could settle down for good.
Well, technically, since Harry was nearly 19 years old, he could get a place of his own.
But he would never leave Snape. After a lifetime of traveling together, as far as Harry was concerned they were stuck with each other.
"Taa. Ta. Ta?"
"Right." gasped Snape, still catching his breath. "Let's get a map and figure out where we'd like to live, eh?"
Snape pulled a map of the world from the top of their solitary bookcase and spread it out on the kitchen table. "Well? What do you think, Harry? Personally, I enjoyed Canada. Mountains, you know."
"I had a good time in Germany, as well, but I'd like to settle someplace where the majority of the population speaks English."
"Yes, Australia was nice. Think you'd like to live there forever, though?"
"Taaaa?" Harry was a bit shocked by that phrasing. It hadn't quite hit him yet that they were now searching for a permanent place of residence, and not a place to crash for a few months.
"We don't have to decide now, you know. We've got the rest of our lives to figure it out." The last thing Snape wanted was to force Harry into a decision he wasn't sure of.
Harry leaned against Snape's back and pondered the map from above his shoulder. Out of all the places they had lived…
"Here." he said calmly as he pointed at a spot on the map, ignoring Snape's choked gasp at the first real word he had ever spoken. "Yeah, here. Home, Sever."
Snape struggled for a moment to pick his jaw up off the floor. He had finally decided that Harry would never speak when he had hit puberty and, after the inevitable "Talk", had flushed a brilliant red and squeaked out a shocked "Taaaa! Ta!"
Snape abruptly wished he had utilized some recording spell, or even had had a muggle video camera handy. His baby's first words, and he had nothing to commemorate the moment. He'd have to go buy a pensieve, he supposed.
"Well," he managed to choke out—oh honestly, he was starting to cry—"you want it, you got it. Let's pack up."
Harry beamed at him. "Taa, Sever. Home."
Light years away, in a million alternate universes, a million different Snapes felt a disturbance in the proverbial Force.
After all, everybody knows that only a Snape in a million actually gets happy enough in their life time to smile wide enough to make their face hurt—and are genuinely happy.
A/N: What, you want to know where they decide to live? Pick your favorite place on Earth and pretend they went there. It's the concept of the thing, you know. --Monopoly