Aang could also be part of this fanfiction. As the Avatar, he might be concerned about the implications of Azula having a baby. He could either be a potential threat if he fears the baby will be raised to be evil, or he could be a source of help, believing that the baby could be a new beginning for Azula and a chance for her to turn good. And Sokka could be there too, maybe providing some comical relief during the more serious moments of Azula's motherhood journey.
Zuko could be involved. He might be initially hesitant about his sister having a baby, but over time, he could come around and offer his support. Another character could be Ty Lee. She has always had a complex relationship with Azula, and in this story, she could be the one who helps Azula with the baby, teaching her some softer skills like how to play with the baby and make it laugh.
Iroh could be an important character. He could offer his wisdom to Azula as she navigates motherhood. He might give her advice on how to raise the baby with good values. Also, Mai could be in the story. She could be a confidant for Azula, listening to her fears and concerns about raising the baby in a world full of political intrigue and danger.
In this fanfiction, the plot might be about Azula's transformation. Having a baby could be the catalyst for her to change her ways completely. She starts off as the somewhat cruel and power - hungry Azula we know, but as she takes on the role of a mother, she gradually becomes more empathetic. The baby could be a symbol of hope for her, and the story could show how she overcomes her inner demons for the sake of her child.
One could be Mrs. Wilder, Almanzo's mother. She could play an important role in giving advice on how to take care of the baby, based on her own experiences of raising children.
Their families could be main characters. Laura's parents might visit often to see their grandchild. Almanzo's siblings could also play a role, perhaps helping out with the farm work so that Laura and Almanzo can focus on the baby.
His mom, Sally Jackson, could be a main character. She might be the one reading the books to baby Percy at first and then be there to answer his questions as he reads on his own later.
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.
Yoshi is a really popular character to include. He can be like a big brother figure to the baby Mario and baby Luigi. He could carry them around on his back and help them reach high places or cross dangerous areas.
Jace would likely be an important character. Given his relationship with Clary, he would probably be deeply affected by the news of the baby. His reaction could range from shock to protectiveness.
There could be Sasuke. Since Sarada is his daughter, he might be in the background, either not aware of the encounter yet or on his way to find Sarada. Naruto could also be a character. He has a connection to both Itachi and Sasuke, and he might play a role in the events that lead up to or follow the encounter. Another possible character could be Sakura. As Sarada's mother, she would be worried if Sarada was out of her sight and her actions to find Sarada could be part of the story.
Definitely Aunt May. She would be super worried about baby Peter and would do everything she could to take care of him. She might even call in some old friends or neighbors to help out.
There could be Glen's best friend who offers advice on how to take care of the baby. For example, teaching Glen the proper way to make baby food.