<p>Adults with greater adverse childhood experiences (ACEs) report greater relational distress and lower relationship satisfaction than those with fewer. Enhanced risk amongst those with more ACEs may be due to increased stress sensitization. Having young children in the home is one period of stress that may operate as a window for intervention to support relational and mental health, particularly for those with a history of ACEs. The ‘Love Together, Parent Together’ (L2P2) program was designed to prevent relationship deterioration amongst couples by teaching conflict reappraisal strategies. The current study is a secondary analysis of a randomized controlled trial of L2P2 to assess whether participation in L2P2 thwarts the negative impact of ACEs on parent mental health (i.e., psychological distress) and relationship quality, respectively. Two hundred eighty participants (nested within 140 couples) were included in the current sample. Participants completed pre-, 1-week-post and 1- and 3-month follow-up surveys measuring ACEs (baseline only), relationship quality (Perceived Relationship Quality Components Inventory), and psychological distress (Kessler Psychological Distress Scale). Couples in the L2P2 group completed three writing sessions to learn and apply conflict reappraisal strategies. Couples in the control group engaged in an inactive writing task. Based on piecewise latent growth curve modelling, ACEs did not predict weekly changes in relational or psychological outcomes in our sample across the study period, nor did the relationship between ACEs and weekly changes in outcomes depend on group assignment (i.e., no significant interaction effects). This study furthers our understanding of the complex relationship between ACEs, parents’ mental health, and relationship quality in the context of a couple intervention.</p>