The aim of this study was to assess stress response symptoms in children of parents diagnosed with cancer 1-5 year prior to study entry. The impact of event scale was used to measure stress response symptoms in terms of intrusion and avoidance; the youth self-report assessed emotional and behavioural functioning; the state-trait anxiety inventory for children measured trait-anxiety. Participants included 220 adolescents (aged 11-18 years) and 64 young adults (aged 19-23 years) from 169 families. Twenty-one percent of the sons and 35% of the daughters reported clinically elevated stress response symptoms. Daughters, particularly those whose mothers were ill, reported significantly more intrusion and avoidance than did sons. Intrusion among daughters was positively related to age. Stress response symptoms in both sons and daughters were significantly associated with trait anxiety, but not with intensity of treatment or time since diagnosis. Daughters whose parents suffered from recurrent illness reported more symptoms than did daughters whose parents had a primary disease. Children (daughters in particular) with clinically elevated stress response symptoms reported significantly more problems of internalising and cognition than did their norm group peers. One-fifth of the sons and more than one-third of the daughters expressed clinically elevated stress response symptoms. These children also reported internalising and cognitive problems. Daughters appeared to be more at risk than sons.