She could also have a different view of the world compared to the Lost Boys. Since she has a connection to the stars, she might see things from a more celestial perspective. This could lead to interesting conflicts and resolutions within the fanfiction. For example, she might think that certain actions the Lost Boys take are wrong according to the stars' 'code' or something similar.
In this type of fanfiction, the star sister might be an outcast like the Lost Boys. They could bond over their shared sense of not belonging. The story could explore how they come together and form a unique family. The Lost Boys might protect the star sister from those who want to use her powers for evil, and in return, she could use her star - related abilities to keep them safe from the sun or other threats.
The sister's character could be developed as a strong - willed individual. For example, if she was raised in a difficult situation, like in an orphanage in the Muggle world, she could have a tough exterior but a kind heart. She might be initially distrustful of the wizarding world when she discovers it, but as she learns more about her family and the fight against Voldemort, she becomes more open - minded and determined to help.
A possible plot is that the lost sister was sent to another dimension by a powerful witch as a means of protecting her from the chaos in the Mikaelson world. In the fanfiction, she grows up in this strange dimension, learning different forms of magic. When she finds a way back to her own world, she meets Hope. Together, they have to face a new enemy that is targeting the Mikaelson family because of their combined power.
One common theme is family loyalty. Despite the strange and often dangerous world of the Lost Boys, the bond between the star and his sister remains strong. Another theme is self - discovery. The sister often has to figure out who she is in this new and wild environment.
A common plotline is the discovery of the sister. She might be found in an unexpected place like a muggle orphanage or a hidden wizarding community. Another plotline is her relationship with Draco. At first, they might be at odds because of their different upbringings, but later they grow closer.
One possible fanfiction idea could be that Bella, as David's sister, has a conflicted relationship with the vampire gang. She might try to keep David from getting into too much trouble while also being drawn to their wild lifestyle. For example, she could be the voice of reason when they plan their hunts, but at the same time, she has her own vampire instincts that she struggles with.
There's a fanfiction that focuses on the sister's unique abilities and how she uses them to protect her star brother. In this story, their bond is tested by various challenges in the Lost Boys' universe. It's a really engaging read as it explores their characters more deeply.
One interesting fanfiction could be 'The Lost Malfoy'. In this story, Draco's lost sister is found to have unique magical abilities that she has been hiding. It shows her journey of trying to fit into the Malfoy family and the wizarding world while dealing with the secrets of her past.
One possibility could be that she shows up at Camp Half - Blood unexpectedly. Maybe she was raised by a mortal family all this time, not knowing about her demigod heritage. When she arrives, she has powers similar to Percy's but also some unique ones, like the ability to communicate with sea creatures in a different way than Percy. This could lead to all sorts of adventures and conflicts within the camp as everyone tries to figure out who she really is and what her role will be.