The characters are mainly the same throughout the movie are the same for the musical. The Maitlands wanted to have a child, but they weren't ready to, and they die in their house. Beetlejuice happened to be watching and give them and introduction to being dead through the songs "The Whole Being Dead Thing" and the second part to that song. Lydia Deetz, just so happened to lose her mother, and so her family with her new mother moves into the Maitland's house. Lydia befriends the Maitlands. Barbara and Adam abandon Beetlejuice, but soon enough so does Lydia with the Maitlands. Beetlejuice eventually befriends Lydia but ends up being betrayed by her. He is eventually re-summoned when the family wont leave the house. Soon enough Lydia goes to the spirit world in order to find her mom, but realizes that she is perfectly fine where she's at with the Maitlands and the Deetz's. She then returns to a happy life by defeating Beetlejuice in the end.