Who could be the main characters in the 'Lily Potter gives birth to a girl' fanfiction aside from Lily and the girl?

One possible plot could be that the girl grows up with unique magical abilities. Maybe she has a special connection to an ancient magic that no one else in the wizarding world has. She could face challenges in Hogwarts as she tries to understand and control her powers, while also dealing with the legacy of her parents.

Harry would often be a main character in these fanfictions. Since it's about bashing his parents, his reaction and how he copes with the new view of them is a big part of the story. Another could be Sirius Black. He was very close to James, so fanfictions might explore his feelings towards the bashing of his best friend.

Petunia could be an important character. She might be grudgingly attending the wedding, still having mixed feelings about Lily's magical world. Her presence could add some tension as she struggles to fit in. And then there's Dumbledore. He could make an appearance and give some wise words of advice to the couple, perhaps about the future challenges they might face together.

James Potter often makes an appearance. Since he was Lily's husband, his relationship with both Harry and Lily is explored in different ways. For example, in some fanfictions, Harry gets to see a side of his father through Lily's memories that he didn't know before.

Hermione would surely be involved. She could be Harry's research partner, helping him find relevant medical information in books and scrolls. Her intelligence and thirst for knowledge would be very useful in exploring new areas of medical magic. Another character could be Madam Pomfrey. She could be Harry's mentor, teaching him the basics of wizarding medicine and guiding him in his new role as a medic.

One possible main character could be a Martian elder who takes Harry Potter under their wing and helps raise him. This Martian elder could have special knowledge about the planet and its hidden magic that they pass on to Harry.

The supreme Mugwump himself could be a main character. He might have his own backstory, motives, and goals that drive the story forward.

Hermione could be a main character. She would probably be very involved in helping Harry with the baby, using her vast knowledge of magic to ensure the baby's well - being.

One potential Quidditch superstar in fanfiction could be a new transfer student. This student could have been a star player in their previous school's Quidditch team and brings a whole new set of skills and strategies to Hogwarts. Maybe they have a unique flying style that no one at Hogwarts has seen before.

Well, first off, Ursula is an obvious main character as she is related to Harry in this fanfiction. Then there's Hagrid. He has always been there for Harry and would likely play a role in helping Harry deal with this new situation. Neville could also be an important character. He might be one of the few who initially believes in Harry and doesn't immediately turn his back on him because of his new identity. And then there are the Weasley family members. They might be a bit hesitant at first but would eventually come around to help Harry as they have always been a big part of his life at Hogwarts.