Living Two Separate Lives

Savannah Hilton is a young girl who looses her father at a very tender age, causing her mother to struggle to care for her and her brother. After 10 years, Savannah and her family move to another state. At such a young age, it was hard for Savannah to be able to associate with people. Apart from her brother, she barely talks to anyone and soon enough, even her brother doesn't have enough time for her. With time, she slowly becomes lonely and doesn't associate with anyone at all. One faithful day, one of her classmates bully her and this incident sticks with her. After some time, news of people going missing spreads and Savannah's mom grows more and more paranoid and doesn't let Savannah or Adam leave the house. Over time, the police get more alert in hopes of finding this mystery killer. They find more clues about the killer and this causes them to run a search around everyone's house in the neighborhood when they find something really strange.
Who could the killer be?