It could be an unknown brother that was kept secret all this time. Maybe he was hidden away by some enemy of the village and trained to be a powerful adversary for Naruto.
Perhaps Naruto's brother could be a long - lost relative from a far - flung part of the ninja world. He could have been separated from Naruto when they were young due to a war or some political intrigue in the ninja clans.
One possible reason could be jealousy. Maybe his brother has some special abilities or gets more attention that Naruto feels he should have. For example, if his brother is really good at a certain jutsu and is always praised for it while Naruto struggles, that could lead to resentment.
In the world of Naruto fanfiction, the theme of Naruto killing his brother does exist. It might be a way for some authors to create a more edgy and different take on the Naruto story. They might rewrite the story's lore and Naruto's personality to make such a scenario possible. For example, they could create a backstory where there is some great conflict between Naruto and his brother that leads to this tragic outcome. This can also be a way to explore different power dynamics and the cost of power in the Naruto world.
One common theme is loyalty. They always show loyalty towards each other, no matter what challenges they face. Another theme is growth. They grow together as shinobi, learning new skills and becoming stronger. And family love is also a big theme. Despite any differences, they love each other deeply as brothers.
Naruto might also be determined to change his brother's mind. He would keep showing his good side, like his kindness and his strong will to protect the village. He could think that by being a better person, his brother will eventually stop hating him. He may even go through some tough training to prove himself not only to his brother but also to the whole village. And in the process, he may face a lot of difficulties and rejections from his brother, but he won't give up easily.
It could be a misunderstanding. Perhaps Naruto was involved in an incident where his actions were misinterpreted by his brother. For example, Naruto might have accidentally caused harm to someone his brother cared about while trying to do something good, and his brother didn't get the full story and started to hate him as a result.
Well, first of all, his abilities should set him apart. He could have a natural talent for genjutsu, while Naruto struggles with it. His personality traits can be explored in relation to Naruto. If Naruto is the sunny optimist, the twin could be the brooding type, with a darker sense of humor. His relationships with the other villagers would also be a factor. He might not be as well - liked as Naruto at first, but as the story progresses, he earns their respect in his own way. Additionally, his reactions to Naruto's fame and how he carves out his own identity within the shinobi world are crucial for developing his character.
Well, sometimes he's depicted as a fun-loving older brother. He'll play pranks with his siblings but also be there when they need him. His status as a hero in the village gives his siblings a sense of pride, and he uses that to boost their confidence. He might take them on adventures around the village, showing them all the secret spots he found when he was younger.
One common way is through loyalty. He'll always stand by his brother no matter what. Another is by listening. He gives his brother his full attention when he has something to say.