A/N: Okay, so this is a theory me and my friend have created that we think should be online, considering somethings we've paid attention to. If you really think about it, this might all be true in some way or another.
Anyway, enjoy, and try not to be to harsh if you wanna debate this. :)
Pokemon Theory: Red is Ash's Father
I know there are theories out there stating that Red was actually Ash's brother, or the games and anime were just completely different in every way. But, what I've come to think, is that Red is actually Ash's father. Why you may ask? Well, let's start simply enough…
Ash is not Red… not by a long shot. He's far more dense and inept in the Pokémon anime than Red was in the game… so they're definitely different. Even Gary and Blue/Green (Whatever people like to call him, for now I'll stick with blue) are different, but I'll get to that later. For now, I will stay on the topic of Red and Ash.
Red started out in Pallet Town, with a goodbye from his mother (Name unknown) much like Ash but among a different circumstance. For one, unlike Ash, he was given a starter – whichever he chose doesn't matter – and of course, Blue chose the opposite to counter Red with types as his power. Red was not fazed and continued on despite Blues obvious dislike over him. Blue had always acted as if he were a superior being, which is why he and Gary are so much alike… but again, I'll get to that later.
Red traveled through Kanto, catching every Pokémon and battling without much fail. Blue would sometimes appear, only to be battled into obscurity later on. He had made his way through the lesser of team rocket, to the elite four, had beaten them without much trouble, and soon became the champion of the Kanto region. He soon found he had done all he could in his homeland and began to wander aimlessly throughout his teen years. From here, he met a young woman, Delia, who they had a child together (And let's remember that the writers of Pokémon did say that Delia had Ash when she was young). So, as young parents, they decided to marry.
Now, on the subject of Blue and Gary, I would have to say that yes the two are much alike… however, in the games, Blue is a very hard-core player that doesn't have much care in the world whether or not your Pokémon are hurt or tired. He will battle you without question. Whereas Gary has much care for his Pokémon and others. Even going as far as becoming a Professor like his grandfather before him to research them. Which is why I believe that Blue is actually Gary's older brother. Their parents – a very young and stupid couple – had Blue when they were in their early teens (So, close to their sixteen's). They raised Blue to the best of their ability along with his twin sister (older by two minutes) but the lack of sufficient parenting made Blue into a bully and somewhat of a sociopath. Why else would he want to battle so eagerly? He wants to prove to his parents that he's good enough.
However, before Ash was officially born, Gary suddenly came into the picture and – not wanting this one to end up like Blue – Professor Oak convinced his parents to give custody of the newborn to himself. This is why Gary is so adamant on making Ash look like a fool in the anime. Because Ash's father had done the same to his older brother. He took away Blue's chances at becoming the best, his sanity, and the love of his grandfather. Gary wanted Ash and his family to pay for making his brother go insane and leave, so he tortured Ash in any way he could. Only until he found out the better meaning to Pokémon, did Gary try to set right to his brother's name. He probably saw what this same path had done to his brother and figured it would be better if he chose a different path, i.e. becoming a Professor and making amends with Ash.
However, this theory is supposed to be about Ash's father… so let us return to the original point.
After Ash was born it was a few months before Red left Delia, promising to come back, so he could train some more. Being the kind woman that she was, Delia agreed that she'd stay home and look after their child. Red truly did care for his family, especially his son, and hoped to come back and teach him all he knew about Pokémon. However, he wanted to train a bit more so he'd have the best Pokémon for his son to learn from. For this, he had to climb Mount Silver. Enduring the cold, harsh climate, fighting wild Pokémon at every chance, he would become the best.
This took a total of four years for him to complete (Since the first gen is 1996 and the second was 1999 - 2000), and he was more than strong enough to face the world. Even more, his son would not be too displeased with him being gone for this long, since he was a newborn when he left. Even if Delia had told him, he couldn't be too upset. He was about to leave and return to his settled life, when… he showed up.
His name was gold… or so he was informed later in the years. And he was strong. Where Red had eight badges, Gold had sixteen. And all his Pokémon were… different from what he was used to. Gold had no troubles with defeating him, and when all his Pokémon had fallen… there was silence. Nothing but the wind and snow crackled through his ears. When a large gust had covered their vision for a split second, Red made his escape. He had failed. He had spent years to become something of pride to his son… and he failed.
He made his way down the mountain. Looking back and making sure no one was following him. He would go back to Pallet town, where his wife and son waited. He would tell them he had won the battle, that he was still champion. No… no he couldn't do that. He couldn't lie to his son… to his wife. Could he hide? Well, he had said to Delia that he was on a journey to get stronger. So… what if he was still on his journey? Delia would still know the truth, and Ash would remain optimistic in his abilities. The boy would still have something to look forward to, and knowing his father was out there training just like him… they would meet up at some point… maybe even have a battle. It was ideal! A win-win!
Delia would always care for Ash, like a good mother would, and Red would keep on training to win back his honour for his boy. Ash would grow, and start a journey of his own. To become the very best like his father before him, despite the many hardships.
The only one who knew of Red's disappearance was Professor Oak, who agreed to keep it all secret. He even went as far as telling Ash that the only Pokémon he had left was a high-strung Pikachu – one his father had sent as a starter for his boy, (Much like in the brother theory) – who, of course, was still attached to Red at the time, so it took a while for Ash to gain Pikachu's trust. This is why Pikachu was so strong, yadda yadda… and so, Red helped Ash as best as he could from what he was able to do without much notice. All the while, Blue still hunted for Red for a rematch of honour, Gary would become Ash's biggest rival, and Ash would try his hardest to follow in his father's footsteps.
Of Course, Red was always there to watch his son battle in the Pokémon leagues (Winning or losing, he cheered him on) But it was not yet the right time to reveal he was around. No… he had to wait until the time was right. Ash would understand… he hoped.