Full context:   Recent studies have begun to explore the developmental origins and trajectories of the Big Five among children and adolescents, especially those that relate to temperament. Many researchers have sought to distinguish between personality and temperament. Temperament often refers to early behavioral and affective characteristics that are thought to be driven primarily by genes. Models of temperament often include four trait dimensions: surgency/sociability, negative emotionality, persistence/effortful control, and activity level. Some of these differences in temperament are evident at, if not before, birth. For example, both parents and researchers recognize that some newborn infants are peaceful and easily soothed while others are comparatively fussy and hard to calm. Unlike temperament, however, many researchers view the development of personality as gradually occurring throughout childhood. Contrary to some researchers who question whether children have stable personality traits, Big Five or otherwise, most researchers contend that there are significant psychological differences between children that are associated with relatively stable, distinct, and salient behavior patterns.