Ron could also be there. He might be in charge of something like the Gryffindor Quidditch team or be a part - time teacher teaching the younger students about the magical history of the Weasley family's inventions. His humor and loyalty would be a great addition to the story.
Hermione is often involved. She would be curious about Harry's new ability and might try to research more about it in the library. She could also help Harry figure out how to use this ability to their advantage in different situations.
Ron could also be a main character. He might be a bit scared or jealous of Harry's new - found ability. But in the end, he stands by Harry. Maybe there's a scene where Ron has to overcome his fear of snakes when they are in a dangerous situation that requires Harry to talk to a snake for help.
Hermione is often involved. Since she's Harry's best friend, she might be the one trying to prevent his death in some fanfictions. Or she could be the one who has to carry on his legacy after he dies.
Dumbledore can also be a significant character. He might be the one who arranges for Snape to teach Harry, having some grand plan in mind. He could be observing from the sidelines, guiding Snape's actions and Harry's progress subtly.
Hermione is often involved. She might help Harry understand the complex magic associated with the Elder Wand. For example, she could research in the library to find out any hidden lore about the wand.
Another important character that is often involved is Hagrid. He might be the one who stumbles upon the forgotten twin sister in her hiding place or he could be the one to introduce her to the wizarding world properly. Then there are the Weasley family members. They could play different roles, like Ginny might become the twin sister's best friend or Fred and George could include her in their pranks and adventures, adding some light - heartedness to the story.
Definitely Hermione and Ron. Hermione would use her intelligence to analyze the situation and come up with a plan. Ron would be the more impulsive one, ready to jump into action. Sirius Black could also be involved. Since he has a history with Pettigrew, he might have some insights into Pettigrew's actions and be able to help in the search for Harry. Also, the Weasley family in general might get involved as they are close to Harry.
Hermione and Ron would most likely be main characters. They are Harry's closest friends in the original story. Since Harry is deaged, they would play important roles in taking care of him or guiding him in some way.
Hermione Granger is often involved. She's Harry's best friend and is extremely intelligent. Her knowledge of spells and magic history can be crucial in helping Harry prove his innocence. She might research old laws or spells that can be used as evidence.
Harry Potter himself is often involved. He might be the one to encounter the first signs of inflation, whether it's a magically inflating potion or an enchanted object. His friends, like Ron and Hermione, are also likely to be part of the story, helping him figure out what's going on.