Normal behavior in children depends on the child's age, personality, and physical and emotional development. A child's behavior may be a problem if it doesn't match the expectations of the family or if it is disruptive. Knowing what to expect from your child at each age will help you decide what is normal behavior.
Children tend to continue a behavior when it is rewarded and stop a behavior when it is ignored.
Consistency in your reaction to a behavior is important because rewarding and punishing the same behavior at different times confuses your child. Attempt to stop the behavior, either by ignoring it or by punishing it. Introduce a new behavior that you prefer. The best way to stop unwanted behavior is to ignore it. This way works best when you're able to wait for results.