Hello, I understand your concern. In order for me to get a clearer picture of the child s behavior in different settings, such as behavior and attention in school (if she does go to preschool) as compared to behavior and attention at home. Hyperactivity does not always equal ADHD and some kids are just gifted with higher levels of energy, but if their activity is frequent and high enough to be disruptive and interfering with normal daily activity, then there is a chance it might be considered a disorder. While in boys ADHD manifests primarily as disruptive and defiant, in girls it is manifests through three types: the hyperactive (tomboys), the inattentive (daydreamers) and the hyperactive-inattentive combo (chatty cathys). At the age of four, when the personality is still being shaped and developed, I think it is too early to determine such a diagnosis. However, when coupled with complete information about her behavior and level of attention in school, a child therapist would have enough information to be able to get a clear picture and determine a diagnosis (if there is one). So please talk to your niece s pediatrician who will be able to give you a referral to see a therapist. Wishing you all the best.