Well, the relationship with his brother would likely be more family - based from the start. James and Sirius were like brothers but they had to build that bond. With a real brother, there could be an innate sense of loyalty that's different. For instance, they might have grown up sharing a room or toys, which would create a different dynamic compared to James and Sirius who met at Hogwarts.
Yes, there are likely fanfictions out there with this concept. There is a large and creative fanfiction community that often explores different family relationships among characters. You can search on popular fanfiction websites like Archive of Our Own or FanFiction.net to find such stories.
One possible storyline could be the brother being a Slytherin while James is in Gryffindor, creating a lot of family tension. They could start off at odds but gradually come to understand and support each other. For example, the brother might initially be involved with some not - so - nice Slytherin groups, but through James' influence and some difficult experiences, he realizes the importance of family and loyalty.
One possible plot twist could be that Harry, as James' brother, has a different role in the fight against Voldemort. Maybe he's more of a behind - the - scenes strategist. Since he's in the family earlier, he could have different relationships with the other characters too. For example, his bond with Sirius might be even stronger as they grow up together more closely.
Well, it could be that Harry, as James' brother, discovers that there were more secrets about his first life than he thought. Maybe he finds out that there was a hidden power within him that was never fully awakened in his previous life. This new discovery could change the way he approaches magic and his role in the fight against the Dark Arts, and it might also lead to a different ending to the battle against Voldemort.
Another challenge is in his relationships. He may worry that people pity him or treat him differently because of his blindness. For example, in some fanfics, he has to prove to Lily that he's still the same James she knew before, just with a new disability to deal with. Also, in duels or battles, not being able to see his opponents' movements directly puts him at a disadvantage, so he has to develop new strategies to defend himself.
He could meet the descendants of his friends, like the grandchildren of Ron and Hermione. They might show him around the future wizarding world and tell him about all the changes that have occurred. Also, he may run into some new and powerful wizards who have emerged in the future and learn from them about new magical techniques.
Another one is 'Potter's Other Son'. In this fanfiction, James Potter's brother is sent on a mission by Dumbledore to infiltrate a group of dark wizards. The plot is strong as it shows his growth from a somewhat overlooked Potter to a key figure in the fight against dark magic. He has to use his intelligence and charm to gain the trust of the dark wizards, all while secretly working for the good side.
One great fanfiction could be 'The Unseen Struggle'. In this, it delves deep into James Potter's psyche during his panic attack. The author might describe his racing thoughts, his shortness of breath, and how he tries to hide it from his friends at first. It shows a vulnerable side of James that we don't often see in the original stories.
Yes, there are likely to be such fanfictions out there. The Harry Potter fandom is vast and diverse, and fans often come up with creative and unexpected scenarios like this. However, the quality and content of these fanfictions can vary greatly.