["Infant Mental Health Journal: Infancy and Early Childhood, Volume 47, Issue 5, September 2026. ", "\nAbstract\nLittle is known about the prevalence of maternal mental health challenges in Khyber Pakhtunkhwa, Pakistan and the ways in which it may influence the development outcomes of young children. This study describes the prevalence of three measures of maternal mental health: depression, anxiety and parenting stress, and assesses whether they independently or jointly predict early child development (ECD) even after accounting for stressors such as poverty, low access to quality education and limited social assistance. A population‐proportionate, cluster‐randomized household survey was conducted collecting data from a total of 1397 children aged 0–35‐months‐old and 705 children aged 36–72‐months‐old and their mothers. Unadjusted and adjusted Ordinary Least Squares linear regression analyses were run for the independent and joint association of maternal depression, anxiety, and parenting stress on ECD. There is a substantial prevalence of mental health concerns among the mothers in our sample—with several mental health concerns co‐occurring. Maternal depression, anxiety, and parenting stress have a significant, negative and compounding interaction on child development for younger and older children, even after controlling for stressors and other covariates. Policy improvements are needed that focus on at‐risk communities, providing mental health services and reducing exposure to stressors within communities and households.\n"]