Arnie is Clark and Marty's son. He is also Luke's brother and Abe's father. Arnie becomes angry when he is told that his son's arm needs to be rebroken and set in order to heal properly. Most of his anger comes from the fear that the operation will put the young boy through more pain. He does not seem to notice that his son's arm is unusable and that the boy will become a cripple if it is not fixed. When Luke tries to talk to Arnie about the surgery, Arnie becomes more angry and pulls away from the family. It is not until Luke apologizes to Arnie for being so pushy about the surgery that Arnie is able to articulate his true fears. He allows his son to decide if her wants the surgery to repair his arm.
