Obviously, baby Quasimodo himself is a central character. Then there's Frollo, who plays a significant role in Quasimodo's life in the original story and would also be important in fanfiction about his baby days.
There could be other characters from the cathedral community, such as the priests and nuns. They would be involved in taking care of baby Quasimodo, teaching him basic things, and being part of his early life in the cathedral.
The gargoyles, like Victor, Hugo, and Laverne from the Disney version, could also be part of the fanfiction. They might be shown as protectors or friends to baby Quasimodo, even if he doesn't fully understand them yet.
Their relationship can be shown through their joint efforts in taking care of the baby. For example, Quasimodo might be very gentle and patient when soothing the baby at night, while Madellaine could be the one who makes sure the baby is well - fed and clothed. Their teamwork in parenting reflects their deep love for each other.
One interesting concept could be exploring baby Quasimodo's early experiences in the cathedral. Maybe how he first discovers the bells or interacts with the kind-hearted people there.
Obviously, baby Rosalina herself is the main character. There might also be her mother or caretaker in some fanfictions. And sometimes, there could be other baby versions of well - known space - related characters like baby Mario or baby Luigi who interact with her.
Obviously, Mikey himself as a baby is a central character. His family members often play important roles too. For instance, his older brothers or sisters who might protect him or play with him.
The baby metroid itself can be considered a central 'character' in its own right. It has its own behaviors and reactions that can influence the other characters around it. For example, its need for energy or its growth spurts might force the other characters to make certain decisions. And of course, there may be characters from the Metroid universe's background lore that show up to interact with the baby metroid situation, like the Chozo who have a connection to the Metroids in the official lore.
In 'bella as a baby fanfiction', apart from Bella and her immediate family, there could be characters who have a special connection to Bella's future self. Maybe there's an old wise woman in the neighborhood who somehow senses that this baby will grow up to be someone special. So she starts to protect Bella from an early age, becoming an important character in the story. And also, if it's set in a particular fictional universe, there could be some creatures or beings that are drawn to Bella because of her unique presence even as a baby.
Well, obviously baby Mew itself is a common character. There are often other Pokémon characters like Pikachu. Pikachu might be a friend or a protector to baby Mew in the fanfiction. Another common character could be a Pokémon trainer. The trainer might find baby Mew and take it under their wing.
Love and acceptance is also a frequent theme. Just like in the original story, but with a different take as a female character. She could be finding love in unexpected places or learning to accept herself through the love of others.
One idea could be that Quasimodo and Madellaine face challenges in raising their baby in a society that is still somewhat prejudiced against Quasimodo's appearance. They have to teach their child to be strong and kind in the face of such adversity.
Another common character could be Supergirl. She might be like a cool older sister figure to baby Conner Kent. She could help him understand his powers better, especially since they both share the Kryptonian origin. She might take him on little flying lessons or tell him stories about Krypton. And of course, there could be other alien characters from Krypton who show up to guide or protect baby Conner as well.