One common supporting character could be Bella's best friend, Lily. Lily is always there for Bella, providing a listening ear and a shoulder to cry on. She might also be the one who gives Bella some practical advice when she's in a tough situation. Another could be Mr. Thompson, an old wise man in the town. He has a vast knowledge of the local history and legends, and he often helps Bella understand the strange things that are happening around her. Then there's Max, a young boy with a special talent for finding hidden things. He teams up with Bella on her adventures and helps her uncover secrets.
There could be other vampires too. Maybe some of Laurent's old friends or enemies. His friends could try to help him and Bella, while his enemies could try to use Bella as a way to get to Laurent. All these characters would contribute to the overall story and the development of Bella and Laurent's relationship.
Alice could be a supporting character. She might have visions about Bella's pregnancy and the future of the baby. Jacob could also be involved, perhaps initially being angry or concerned about Bella's situation with Aro. Carlisle could be another one, as his medical knowledge as a vampire doctor could be useful in dealing with Bella's pregnancy.
Bella is the main focus, of course. If it's in a crossover fanfiction, other characters from different fictional worlds could be included. But in a more traditional setting, characters like Rosalie might be there. Rosalie, with her own experiences related to motherhood or the lack thereof, could have a complex relationship with Bella during her pregnancy. Alice might also be a common character, using her ability to foresee things related to the pregnancy, like whether it will be a smooth process or if there are any upcoming challenges.
Carlisle, being a doctor in the original story, would be a very relevant character in Bella surgery fanfiction. He could be the one performing the surgery, and his medical expertise and ethical considerations would play a big role in the story. Also, other members of the Cullen family might be around, providing support or having their own thoughts about Bella's surgery.
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.
Edward's family members might also be supporting characters. For instance, his sister could come to the office and befriend Bella, or his father who might have some influence on the business that affects Bella's and Edward's relationship.
Their best friends could be great supporting characters. For example, Bella's best friend might help her with choosing the wedding dress, giving her advice on how to deal with pre - wedding jitters. Paul's friend could be the one who organizes a wild bachelor party but also stands by him during the nerve - wracking moments before the wedding.
Edward would be an obvious choice as a main supporting character. He would be there for Bella, sharing in her joys and fears, and helping with all the preparations for the twins. Another could be Alice. She might use her ability to foresee things to help Bella prepare for any challenges during the pregnancy.
One possible supporting character could be Stefan. Since he is Damon's brother in the Vampire Diaries universe, he might play a role in the fanfiction. He could be either supportive of their relationship or a bit hesitant at first.
Charlie, Bella's father, would probably be a significant supporting character. He might be initially shocked but then come around to support Bella and Jacob in raising the baby. The wolf pack could also be important. They might offer their protection and guidance to Jacob as he becomes a father.