for The Pigman's Legacy by Paul Zindel
This is the sequel to The Pigman, one of the bestselling young adult books of all time. John and Lorraine happen to be passing by the Pigman’s abandoned house when they receive the shock of their lives: someone or something is watching them from the upstairs window. Convinced this is a sign from beyond the grave, John and Lorraine decide they have been given a chance to make up for what happened to the Pigman. Can they make things right once and for all?
Publisher description retrieved from Google Books.