Learning about behavioral problems experienced by other members of the family makes it possible to see patterns of inheritance of the behaviors involved. For example, a child with motor or vocal tics of TS may have relatives with ADHD, alcoholism, Obsessive-compulsive behavior, etc. Tourette's Syndrome is not an isolated ailment, it has many co-occurring conditions. This is the most common symptom of TS, after vocal and motor tics. It is often associated with conduct disorder and learning disorders.
Children often develop ADD first and tics later.
Obsessive-compulsive and ritualistic behaviors, such as touching things with both hands, counting or checking things, perfectionism, hand washing, head banging, biting or hurting oneself, touching sexually, mimicking others, shouting inappropriately, obsessive unpleasant or silly thoughts. These types of behavior occur in about half of TS cases. Conduct disorder, including oppositional behavior, talking back, discipline problems, refusal to listen, aggressive and defiant behavior, unprovoked temper tantrums. He also notes that almost all adults with antisocial personality were also antisocial as children, and that this is due to inheritance of a disinhibition gene or genes. Depression, including manic depression, with wide mood swings.