Moral development in children involves their thoughts, feelings, behaviors, and personality as they learn what proper attitudes and behaviors are around others. There are several theories of moral development. Piaget's theory includes stages where young children see rules as unchangeable, then understand rules are man-made. Kohlberg's theory includes stages where young children's reasoning is based on obedience or punishment, then moves to more conventional reasoning and finally postconventional reasoning judged by moral concerns. Moral development also involves empathy, peer interactions, prosocial behaviors, and the development of moral personality and character over time.