Odd behavior refers to behavior that is unusual or unexpected, and may be a sign of an underlying issue. Oppositional defiant disorder (ODD) is a type of behavior disorder that can cause extreme anger, irritability, and defiance towards authority figures, such as parents and teachers. Children with ODD may argue frequently, refuse to follow rules, and deliberately annoy or upset others. Other symptoms of ODD may include blaming others for their own mistakes, being vindictive, and having frequent temper tantrums. ODD can cause serious problems with family life, social activities, school, and work. It is important to note that some oppositional behavior is normal during certain stages of development, but ODD involves a frequent and ongoing pattern of negative behavior that lasts at least six months. The causes of ODD are complex and may involve a combination of factors, such as temperament, parenting, genetics, and environment. If you are concerned about your childs behavior, it is important to seek help from a healthcare provider, mental health professional, or child development expert.