Studying Childhood-onset Behavioral, Psychiatric, and Developmental Disorders

Background: \- Many psychiatric, behavioral, and developmental disorders are genetic. This means that they tend to run in families. Some begin in childhood, while others do not appear until adulthood. Researchers want to look at people of all ages who have these disorders that started in childhood. They will also look at relatives of people with these disorders. This information will allow doctors to learn more about childhood behavioral problems and how they are inherited. It may also help doctors treat those disorders. Objectives: \- To study the onset and treatment of childhood behavioral, psychiatric, and developmental disorders. Eligibility: * Individuals of any age who have a psychiatric, autism spectrum, or developmental disorder, or other behavioral problems. * Family members of individuals with the above disorders. This group may include parents, grandparents, siblings, aunts/uncles, cousins, and children. Design: \- Participants will be screened with a medical history and physical exam. They may have a psychiatric history with tests of thinking, judgment, and behavior.

* INCLUSION CRITERIA: Participants will be eligible if they: 1. Are 30 days to 99 years old. 2. Either: -Have a diagnosed neuropsychiatric disorder or neurodevelopmental disability or related symptoms without a formal diagnosis OR -Are a biological relative of someone who meets the criteria above. 3. Have the ability to understand and sign an informed consent on behalf of themselves, or have a legal guardian (or designated DPA). 4. Are under the care of a primary physician. EXCLUSION CRITERIA: Participants will not be eligible if they: 1. Are unwilling or unable to be evaluated and followed as clinically indicated. Examples might include children with severe behavioral problems who refuse physical examination. 2. The participant does not have a primary healthcare provider.