Another way is if his sister has some special powers that she can't fully control yet in the fanfiction world. And during a training session or an accidental encounter, her powers lash out and end up hurting Naruto.
Well, Naruto could also seek support from his friends like Sasuke or Sakura. They have been through a lot together, and they might be able to offer him some comfort and advice on how to handle this difficult situation. Since Naruto values his friendships highly, their words could have a big impact on him.
It could be that Anko is under some sort of mind - control in the fanfiction. And because of that, she attacks Naruto without really meaning to. Maybe she has been influenced by an enemy's genjutsu. So, she uses her powerful attacks on Naruto, and he gets hurt as a result.
Maybe she's jealous of Naruto's popularity or his strength. It's possible that she feels overshadowed by him all the time and that jealousy turns into resentment, leading her to hurt Naruto.
In some fanfictions, Sakura might accidentally hurt Naruto during a training session. Maybe she uses a new jutsu she's not fully mastered and it goes wrong, hitting Naruto instead of the target.
In some fanfictions, Percy's sister might hurt him emotionally by betraying his trust. For example, she could share his secrets with others, making him feel exposed and betrayed.
She could be very sad. After all, Naruto is likely an important person in her life. She might feel abandoned and start to question why Naruto left her.
In some fanfictions, Naruto might show his love for his sister by protecting her at all costs. For example, he would stand in front of any danger that comes her way, just like how he protects his friends in the original story.
In such a fanfiction, Naruto could die in various ways. Maybe his sister is somehow possessed and attacks him fatally. Or there could be a situation where she accidentally causes his death during a fight due to a lack of control over her power.
In fanfiction where Naruto is hurt by his family, it can have a profound impact on his character development. Firstly, it could make him more withdrawn and distrustful. He might start to question his self - worth as family is supposed to be a source of love and support. For example, if his parents were alive but rejected him, he could become bitter. This could also lead to him being more self - reliant, relying less on others and more on his own strength. He may develop a tough exterior to hide his pain, but deep down, the hurt would still be there, influencing his actions and decisions in the story.
One reason could be jealousy. If Naruto is getting more attention or has achieved more in the ninja world, his sister might be jealous and this could lead to her actions that hurt Naruto, either by spreading false rumors or directly confronting him in a hurtful way.