These behaviors are mostly directed towards an authority figure such as a teacher or a parent. Although these behaviors can be typical among siblings they must be observed with individuals other than siblings for an ODD diagnosis. Children with ODD can be verbally aggressive. However, they do not display physical aggressiveness, a behavior observed in conduct disorder. Furthermore, they must be perpetuated for longer than six months and must be considered beyond a normal child's age, gender and culture to fit the diagnosis. For children under 5 years of age, they occur on most days over a period of 6 months. For children over 5 years of age they occur at least once a week for at least 6 months. It is possible to observe these symptoms in only 1 setting, most commonly home. Thus the severity would be mild. If it is observed in two settings then it would be characterized as moderate and if the symptoms are observed in 3 or more settings then it would be considered severe.