What to read after William and the Lost Spirit?

William knows his father is dead. Everyone knows it . . . everyone except William's sister, who hears him calling to her. Despite William's warnings, she disappears in the night to find their father. To rescue his sister, William must travel through dangerous forests swarming with bandits. But human foes are the least of his problems. His quest will take him beyond the world he knows and into far-off lands—where monsters are real, the dead can speak, and lies become truths. With an enchanted goat as his guide, William follows a strange path that may lead to his sister . . . and perhaps his father as well.