In some versions of this fanfiction, it could be Neville. He also had a difficult family situation, so he might be more attuned to signs of distress in Harry. Maybe he notices Harry's worn - out clothes that are too big for him, which could be a sign of neglect, and then starts to piece together that something is wrong at the Dursleys'.
Well, first of all, the students would probably be shocked. His friends, like Ron and Hermione, would be extremely angry at the Dursleys. They might try to comfort Harry more often. And the school itself could start providing special resources for Harry, such as counseling or extra protection spells. Also, there could be a big change in the way the wizarding community views Harry. Instead of just seeing him as the 'Boy Who Lived', they would see him as a victim who needs support.
In some fanfictions, Harry might discover that students at Hogwarts are being abused by certain dark forces or corrupt individuals. For example, there could be a fanfic where a new dark wizard has infiltrated the school and is using dark magic to mentally or physically abuse students. Harry could discover this through seeing the strange behavior of the victims or finding some clues around the school.
The discovery of the abuse might make Harry more empathetic towards other students who have had difficult pasts at Hogwarts. He could become a sort of advocate for those who are bullied or mistreated. Also, it could affect his relationship with his teachers. Some teachers, when they learn of his past abuse, might be more lenient or offer more support, which in turn helps him grow and develop at Hogwarts.
Severus might initially be shocked. He could then feel a sense of protectiveness over Harry. He might start to secretly look out for Harry, like making sure he has enough to eat at Hogwarts and is safe from further harm.
Some might be shocked and sympathetic. For example, Hermione would likely be very empathetic and immediately start thinking of ways to help Harry. She might offer her support in terms of studying magic that could protect him or just be there to listen.
His friends like Ron and Hermione would surely be there to assist him. Ron could use his strategic thinking and Hermione her vast knowledge of magic. They might come up with a plan to expose Umbridge's wrongdoings which would lead to her being kicked out. Also, the Weasley twins could play a big role. They are known for their pranks and could use their creativity to make Umbridge's life at Hogwarts so miserable that she'd have no choice but to leave. And Dumbledore, even if he has to be a bit more subtle in his actions, could give Harry some guidance behind the scenes.
Well, if we consider the 'umbridge finds out harry was abused fanfiction', it really depends on the writer's take. One possibility is that Umbridge, being the power - hungry character she is, might try to cover it up to maintain the status quo at Hogwarts. On the other hand, she could also see it as a way to discredit Dumbledore, thinking he failed to protect Harry. There's also a chance that the discovery could lead to a change in Umbridge's relationship with Harry, from being a tormentor to an unexpected ally, though this would be a huge shift in her personality.
😋The novel I recommend to you is A Magical Cat from Hogwarts. In it, Harry is an abused child, and his first friend at Hogwarts is Zabini. I hope you like this fairy's recommendation. Muah ~😗
In some fanfiction, Harry's abuse before Hogwarts is shown through his physical appearance. He may be depicted as undernourished, with bruises that he tries to hide. For example, he might always wear long - sleeved shirts to cover up the marks on his arms.
One possible answer could be that in some fanfictions, it might be Dumbledore who first notices the signs of abuse. He might see Harry's withdrawn behavior or the way he flinches at sudden movements, which are typical signs of an abused child. This could lead to Dumbledore taking immediate steps to remove Harry from that situation and bring him into the wizarding world earlier than in the original story.