In Hogwarts, it would be a wild change. Draco would be super conflicted. He's been taught to look down on Gryffindors and half - bloods like Harry. But with Harry as his brother, he'd have this internal struggle. Harry would probably be more open to Draco than Draco is to him. Harry would hope to convert Draco to a more accepting way of thinking. There would be times when Draco would be mean to Harry in public to keep up appearances, but in private, he might start to question his own beliefs because of their relationship.
If Harry were Draco's older brother in this fanfiction, their relationship at Hogwarts would be a total mess - up of the original dynamic. Harry would be constantly torn between the Gryffindor values he adheres to and his family bond with Draco. Draco might start to question his Slytherin - only ideology because of his connection to Harry. For example, they might find themselves in situations where they have to choose between their house loyalties and their new - found brotherly bond, like during the Quidditch matches or the Triwizard Tournament.
Their relationship could change Hogwarts in many ways. For one, they might form an alliance against common enemies within the school, like bullies or those who promote pure - blood supremacy too aggressively. This could lead to a more united front among the students. Also, their friendship (if it develops) could influence house rivalries. Gryffindor and Slytherin might not be as divided as before. Students might start to see that there are good people in both houses and that family bonds can transcend house differences.
They could form a sort of alliance. Harry, being the hero figure, could bring Draco into his circle of friends more often. Draco, with his Slytherin knowledge and connections, could help Harry in understanding some of the more mysterious aspects of Hogwarts, like the secrets of the Slytherin common room. Their relationship could bridge the gap between Gryffindor and Slytherin, changing the whole dynamic of the houses at Hogwarts.
It could make Draco feel exposed and vulnerable at first. But if Hogwarts uses the knowledge from his memories to help him, Draco might develop a newfound respect and loyalty towards Hogwarts. He could see it as an entity that truly cares about him rather than just a place of learning.
Their relationship would likely become more collaborative. They would have to communicate regularly about Teddy's needs, like his schoolwork, his magical training, and his emotional well - being. This would force them to put aside their past grudges and start seeing each other in a new light.
At first, their relationship might be full of confusion. They've been brought up with different values - Harry with his Gryffindor courage and sense of justice, and Draco with Slytherin pride and ambition. But as they discover they're twins, they'd start to see the similarities in themselves. They might begin by being a bit hostile towards each other, but gradually, as they face challenges together, like dealing with a particularly tough teacher or a dangerous creature on the grounds, they'd form a bond.
If they were friends before Hogwarts, it could create a lot of internal conflict at Hogwarts. Draco might be torn between his new Slytherin friends who dislike Harry and his long - standing friendship with Harry. He might try to keep their friendship a secret, which could lead to misunderstandings between them.
Towards the end, their relationship could become a very strong and unique one. They could be each other's closest confidants, with Harry being the one Draco turns to when he has doubts about the pure - blood ideology, and Draco being the person Harry trusts to keep him safe in the Slytherin common room. Their bond would be a mix of brotherly love and mutual respect.
Well, it would completely change their relationship. For one, Draco might be more protective of Hermione. He might not be as mean to her as he was in the original story. He could use his Slytherin influence to shield her from some of the nastier Slytherins. Instead of the constant bickering, they could have a more brother - sisterly bond where they secretly look out for each other. For example, Draco could help Hermione with some of the pure - blood politics she doesn't understand while Hermione could help Draco with his studies.
Their relationship would likely become more collaborative. They would have to put aside their past differences for the sake of their son. Instead of being rivals, they would become partners in parenting. They would need to communicate more often about their son's upbringing, which would force them to get to know each other better on a personal level.