Girl in the Wall
The girl is the daughter of Rebecca Gibson, who was raped by her father Bill Gibson and then hung herself. She and her brother have been kept captive by Bill Gibson their whole lives, living in the basement and the walls of the house and subsisting on scraps they were fed and eating rats. Eventually they escape and kill Bill Gibson. When the Carter family moves in, they start terrorizing the family. The girl is finally stabbed by Brian Carter as she attacks Susan Carter and her daughter. The boy is shot when he attacks Dean.