The longitudinal relationship between child emotional disorder and parental mental health in the British Child and Adolescent Mental Health surveys 1999 and 2004

•Child emotional disorder is associated with later parental poor mental health.•Parental poor mental health is associated with later child emotional disorder.•Relationship mediators need investigation for potential risk/protective factors.•Professionals need to consider the wider family impact of emotional disorders.•Services should consider how to work together to support individuals and families.