Objectives Young people's perspectives on the association between having a family member with a chronic health concern (FHC) and their own health are under-researched. This study used young people's reports to assess the prevalence of FHCs and their association with negative health outcomes, with an aim of identifying potential inequalities between marginalised and non-marginalised young people. Family cohesion was examined as a moderating factor. Design Cross-sectional data from the Australian Child Wellbeing Project survey were used. Respondents were asked whether someone in their family experienced one or more FHCs (disability, mental illness or drug/alcohol addiction). In addition, their experience of different psychosomatic symptoms (headache, sleeplessness, irritability, etc), aspects of family relationships and social and economic characteristics (disability, materially disadvantaged and Indigenous) were documented. Setting Nationally representative Australian sample. Participants 1531 students in school years 4 and 6 and 3846 students in year 8. Results A quarter of students reported having an FHC (years 4 and 6: 23.96% (95% CI 19.30% to 28.62%); year 8: 25.35% (95% CI 22.77% to 27.94%)). Significantly, more students with FHCs than those without reported experiencing 2 or more negative health symptoms at least weekly (OR=1.78; 95% CI 1.19 to 2.65; p