Although exposure to interparental conflict (IPC) in late childhood and adolescence appears to be a robust risk factor for the development of child psychopathology, less work has examined how very early exposure to IPC poses risk for the development of psychopathology in the first 2 years of life. Further, it is unclear whether IPC is uniquely related to child psychopathology relative to other critical dimensions of the interparental relationship. This study aimed to investigate the unique effects of IPC and low levels of emotional intimacy in the interparental relationship during pregnancy and infancy on toddler psychopathology and whether children with higher negative emotionality during infancy were most vulnerable to these conditions. One hundred fifty-one cohabitating couples completed semistructured interviews and questionnaires once during pregnancy and three times postpartum. Results demonstrated that consistent and sustained interparental emotional intimacy, first observed during pregnancy and persisting throughout infancy, was a unique predictor of toddler psychopathology, controlling for sustained and persistent exposure to IPC. The negative association between emotional intimacy and toddler general psychopathology was stronger at higher levels of infant negative emotionality. Results highlight the importance of early exposure to a warm, affectionate interparental relationship for healthy child socioemotional development. These findings have potential for informing early prevention and intervention efforts, including prenatal programs, aimed at reducing psychopathology across the lifespan. (PsycInfo Database Record (c) 2024 APA, all rights reserved).