The increasing prevalence of mental health difficulties is a concern placing strain on health services. Figures indicate Ireland shows high prevalence rates for adults compared to international estimates (Hyland et al., 2022), referrals to child and adolescent mental health services in Ireland has increased in the wake of Covid-19 (McNicholas et al., 2021). Such difficulties are partially transmitted within families, with parental psychopathology shown to predict the incidence, severity and persistence of mental health difficulties amongst children (Costello and Maughan, 2015). This project aims to address trends in mental health prevalence by examining how within-family concordance of mental health difficulties may be understood through variation in parental mind-mindedness. Parental mind-mindedness refers to the propensity to think of one’s child as an agent with an independent mind (Meins, 1999). Studies show that parental mind-mindedness is linked to child and parent and child psychopathology (Larkin et al., 2025; Sharp & Fonagy, 2008). Studies traditionally focused on parent or child outcomes rather than examining mind-mindedness linking the two. This study adopts a family systems perspective to examine associations between parent and child mental health and the mediating role of parental mind-mindedness. Data will be collected from a community sample of parents of children aged 3-12 years via online survey and phone interviews involving standardised questionnaire measures of adult and child mental health and a speech sample procedure to capture representational mind-mindedness. Controlling for family background variables (family form, socio-economic status, child age, parent gender), associations between parent and child mental health symptomology will be examined. Mediation analyses will test the role of parental mind-mindedness in explaining within-family associations. This dual focus on parent and child mental health will facilitate insights into within-family transmission of symptomology and have the potential to inform future strategies to promote population health at the family level.