It could be that Mewtwo's little brother is a key to unlocking some new mystery in the Pokemon world. Maybe there are secrets related to their creation that only he can uncover. As they explore together, they face off against other powerful Pokemon or humans who want to use them for their own gain. This would lead to a lot of action and drama in the fanfiction.
Well, the story could be about Mewtwo's little brother being created in a similar way as Mewtwo. Maybe he has different powers or a different personality. He could be more naive and curious about the world compared to Mewtwo who has already gone through a lot. And they could go on adventures together, facing challenges and learning about each other.
The plot could be about Naruto's little brother growing up in Naruto's shadow. He might struggle to find his own identity while constantly being compared to Naruto. Maybe he has different ninja abilities that are overlooked at first because everyone is so focused on Naruto's power.
The relationship could develop in a very emotional way. Mewtwo's little brother could be a source of warmth and hope for Mewtwo, who has seen so much darkness. Mewtwo would gradually open up to his little brother, sharing his past traumas. In return, the little brother would offer unconditional love and support. They would become inseparable, and their bond would be unbreakable as they face the challenges of the Pokemon world together.
Perhaps in the fanfiction, the little brother has some special abilities that are different from Mewtwo's. This causes a bit of a stir in their world. Mewtwo has to help his little brother understand and control these powers. They might face some villains who want to use the little brother's powers for their own gain. Mewtwo and his little brother would then have to fight together to protect themselves and their world.
There could be other Pokémon like Pikachu. Pikachu could be their friend who helps the little brother adjust to the new world. He could also offer some comic relief in the story. Another possible character could be Ash. Ash has a lot of experience with Pokémon, and he could offer some guidance to Mewtwo on how to take care of his little brother.
One possible plot could be that Harry's little brother discovers he has a special power too. Maybe he can communicate with magical creatures in a unique way. This would lead to all sorts of adventures, like helping Hagrid with some difficult magical beasts that are causing trouble in the Forbidden Forest. He could also use this power to make friends with creatures that could assist Harry and his friends in their battles against Voldemort.
One possible plot could be that Harry's brother has been hidden away all this time due to a powerful dark magic spell. As the story progresses, Harry discovers his brother's existence and they have to team up to fight against a new dark wizard threat that is rising in the wizarding world. Their combined powers, with Harry's experience and his brother's unique abilities, are the key to saving the day.
One possible plotline could be that Naruto's brother has been living in secret all this time. Maybe he was sent away for his own safety when they were young. He could return to the village and at first Naruto is suspicious, but as they get to know each other, they form a strong bond and fight together against the common enemies of the village.
The taller little brother story could be a heartwarming tale of how this little brother uses his height to protect or help others. He could be the one who always gets things from high shelves for his family members. Or it might be about his growth not just in physical height but also in character, and how his height is a part of his identity that shapes his relationships and experiences.
Perhaps the older brother was once the heir apparent in the Malfoy family but something happened that made him lose his status. This could be due to a failed mission for the Dark Lord or a disagreement with his parents. Draco would then be in a position where he has to prove himself even more, while also trying to understand what happened to his brother and if he can help him regain his former position.
One possibility is that the younger brother could be a source of both chaos and unity. He might be initially jealous of Thor and Loki's fame and power, causing some internal family strife. For example, he could try to outdo them in heroic deeds in a rather clumsy way, leading to comical situations. But in the end, when faced with a great threat to Asgard, he realizes the importance of family and uses his unique skills, perhaps some kind of hidden magic or strategic thinking, to help Thor and Loki save their home.