(England, Earth)
It was over time that Tom realized he was a child again.
Which was just as well. He was afraid that his next memory would be getting ejected out of some woman's womb. Or getting suckled on her tits. But it seems that it takes some time before a human child can master the fine art of making sense of its own thoughts, which is why he was spared that particular indignity. By the time he could truly claim to have woken up, he was four years old, and already knew a few things about his new life.
He was Pollux, twin brother of Castor. They were both born on 26th July 1979. They lived with "mother" and "dad". They had an older sister "Nimi" who was ten years old.
It seemed mother was a pureblood, while dad was a muggleborn. Pollux wondered how that had happened along. He wryly thought that at least it was a step-up from his previous life... his father was a wizard this time!
Four year olds have a lot of spare time. Playing with his toys took only a fraction of his brain, and he used the time to think. He still had no idea what he was going to do with his life, beyond "don't be a dark lord". He supposed restoring the former glory of the Slytherin name was right out... he hoped his ancestor's ghost forgave him for that.
He was actually enjoying being a child. His most recent thoughts previously were filled with guilt and remorse; in contrast the complete irresponsibility of his life now was almost cathartic. He supposed that was the plan - he became a dark lord because of an unhappy childhood, so with a happy childhood he wouldn't become a dark lord.
(It completely escaped his thoughts right then that Harry Potter had also had a less than wonderful childhood and still didn't turn out to be a dark lord.)
This would be easy, wouldn't it? He would be a happy child, and happy children don't become dark lords. He was smarter than anyone else in the world - and in a world without a dark lord (since he was not about to become one) there would really be no trouble at all.
He knew he was probably tempting fate by thinking like this, but he couldn't help it. Sure he would face the little problems all the normal people faced, but it would be no trouble for he who was once Tom Riddle.
For what was probably the first time in either of his lives, Pollux relaxed. He had some of the best days of his life as a child.
After Nimi (turns out her name was Nymphadora. Who names their kid Nymphadora?) went to Hogwarts a year later, Pollux found himself with even more time on his hands. He decided to use the time to assess some of the magical talents of his new self.
For example, was he still a parselmouth? Parseltongue was a blood trait, and best known amongst the direct descendants of Salazar Slytherin. But Slytherin was not the first parselmouth; he was merely the best known. Magical people who shared an ancestor with Slytherin could also develop the talents of parsel speech.
It was pretty unlikely, but the only way to find out was to try talking to a snake.
But the trouble was, a five year old versus a snake could turn out to be pretty fatal for the five year old if it turned out he could not talk to snakes. There had to be some sort of control.
He made all sorts of attempts to find snakes in circumstances where they could not harm him. He begged his parents to take him to the zoo once. He was disappointed to find that the zoo had no snakes. What sort of zoo has no snakes? Were they bloody extinct in this world?
He made plans to trap a garden snake in a glass jar and safely question it. It was a very good plan; it had fallbacks on top of fallbacks. Tom Riddle didn't make plans halfway, and neither did Pollux. And like several of his excellent plans he never got a chance to use it.
Because one day the bedroom of Pollux and Castor was invaded by a black snake.
He was more frightened than he had ever been in his life. Er, lives. He climbed on top his bed, and deciding he had nothing to lose, talked to the snake.
"Hello, can you hear me?"
There was no reply from the snake which continued to slither at him menacingly.
"You on the ground. Black snake. Stop right now!"
Still no response.
It became pretty obvious the snake did not understand Pollux, and judging from the way its hisses were just hisses, Pollux did not understand the snake either. He knew it was unlikely he'd be a parselmouth again, but this had to be the worst way of finding out!
"So, can you speak to it?"
Pollux turned to see Castor leaning casually against the door, watching Pollux with no expression on his face. He did not seem even a bit frightened of the snake, which for its part seemed to ignore Castor and continued to advance on Pollux.
"No, I can't speak to the snake!", Pollux replied desperately.
Castor grinned, stood up straight to bring forth a knife he must have tucked in his waistband before and casually decapitated the snake by stabbing its neck.
While Pollux was still catching his breath Castor disposed of the snake's body and cleaned up the blood. He cleaned up the knife and placed it back in the kitchen. Finally he disposed off of the rag he had used to clean up the blood.
When Castor came back to the room Pollux had calmed back down and was watching Castor warily. Pollux had till now ignored his twin as a five year old of no consequence, but an average five year old did not have instincts of a remorseless professional killer.
Well, he did. He'd had it the first time as well.
"Why'd you kill the snake?" he asked Castor, although he felt it was a stupid question as soon as he'd asked it. There were other better questions he could have asked. For example, how did the snake get in? Castor did not seem surprised to see the snake...
Castor looked at him making it obvious he thought it was a stupid question. "If I hadn't killed it it would have killed you."
Pollux also realized something else... Castor was not a stranger to the idea of people speaking to snakes. He'd asked Pollux if he could speak to the snake, but Pollux had not asked Castor if he could.
Then he smiled a lopsided smile which didn't reach his eyes "Besides, I hate snakes."
Pollux was reminded of another five year old boy nearly fifty years ago who was pretty scared of snakes; that is, until he realized he could talk to them and make them do his bidding. This sounded like Tom Riddle would say.
How Castor looked at him was how Tom Riddle would look at people.
How Castor had acted was how Tom Riddle would have acted.
Castor was the twin brother of Pollux, who was Tom Riddle in another life. They were both named after the Gemini, which is the constellation for twins.
Was Castor Tom Riddle as well?