Professor Stephen Pilling told Daybreak that children with conduct disorder require a "different way of parenting".
He added that families are not to blame when children are challenging, but parents do need help to get the best out of their child.
More top news
A judge who was reunited with an old school friend standing before her in the dock encountered another familiar face in her court room.
Campaign backed for u-18s' right to delete damaging or embarrassing social media posts that could cause problems later in work or education.
Investigation into crashed Virgin Galactic test flight finds human error is direct cause, but points to a number of failings in preparation.