One possible plotline could be that Petunia has a sudden realization of how unfairly she has treated Harry over the years and tries to make amends. She might start by secretly helping him with things around the house or protecting him from Dudley's bullying.
A plotline could involve Petunia having a change of heart due to a magical event. For instance, she might accidentally stumble upon some of Harry's magic or receive a message from the wizarding world about his importance. This could lead her to stand up against Vernon and protect Harry. She could then start to teach Harry about his mother's side of the family and the magic that runs in his veins in a more positive way than the Dursleys ever did. And perhaps she even helps him develop his magic skills secretly before he goes to Hogwarts.
One possible plotline could be that in an alternate universe, Petunia and Sirius meet under different circumstances. Maybe Petunia has a more magical inclination than in the original story, and Sirius sees something in her that draws him to her. Their relationship then develops against the backdrop of the wizarding world's politics and the ongoing struggle against the Dark Arts.
Well, a possible plotline might be that Harry saves Narcissa during a dangerous situation in the wizarding war. This act of heroism makes Narcissa see Harry in a new light, and he in turn is drawn to her vulnerability. As they interact more, their relationship blossoms. Or, it could be that they are brought together by some magical force or prophecy that they initially resist but eventually give in to their feelings.
Yes, there are some out there. You can start by looking on fanfiction platforms like FanFiction.net or Archive of Our Own. Some writers might explore an alternate universe where Vernon and Petunia show love towards Harry in a more positive way, perhaps due to a change in circumstances or a different understanding of his situation.
Well, often you'll see themes of forgiveness. Harry might have to forgive Aunt Petunia for her years of mistreatment, and in turn, she has to forgive herself. There can also be a theme of love against all odds. Despite the circumstances and her initial dislike, Aunt Petunia discovers a deep love for Harry. Additionally, some stories may explore the theme of changing perspectives, where both characters see each other in a new light.
One possible plot could be that Harry shows a special talent early on that Vernon and Petunia recognize as something extraordinary. This makes them see Harry not as a burden but as a valuable part of the family. They then start to love and protect him, and this changes Harry's life completely. He no longer has to endure the abuse and neglect he faced in the original story.
One possible plotline could be that Harry discovers he has a half - brother he never knew about. Maybe his father had a relationship before he met Harry's mother, and this new character enters Harry's life. They initially have some conflicts due to jealousy or differences in upbringing, but over time, they come to love and support each other.
One possible plotline could be that Harry discovers a magical doll during one of his adventures. This doll has some special power or connection to his past, and his love for it grows as he tries to figure out its mystery. Another could be that he starts collecting dolls as a way to remember his lost loved ones, and the dolls become a source of comfort for him in the dangerous wizarding world.
One possible plotline could be Petunia struggling to make ends meet while raising Dudley on her own. She might have to take on extra jobs in the Muggle world, and this could lead to some interesting interactions with her neighbors. Another could be her dealing with Dudley's magical abilities (if he has any latent magic), which she has no idea how to handle.
Yes, there are some. You can check fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Aunt Petunia loves Harry' and you'll likely find a variety of stories, some exploring her hidden affection for Harry in different ways, such as through moments of unexpected kindness or a deeper understanding that develops over time.