Hello, I have a question regarding how ADHD is inherited.  Can a father with ADHD inattentive without hyperactivity have one child with ADHD with hyperactivity, impulsivity and one child with ADHD inattentive without hyperactivity.  Is there a separate gene for each type of ADHD?  I am wondering because my husband has ADHD inattentive and each of my children have a different type of ADHD.  My son age 11 presents just like my husband, quiet, inattentive, lack of initiative.  My daughter age 8 is loud, hyperactive, interested in everything and is driven by a motor.  I suspect that my brother has ADHD and he is loud and hyperactive.  So maby my son inherited it from my husband and my daughter inherited from my side of the family?