Children's emergent language develops in a rich context of varied influences afforded by their familial and social environments. Using data collected during a longitudinal prospective service project, this study examined the direct and indirect contributions of parenting knowledge and practices and maternal postnatal depression on emergent language competencies of 198 very young children in high-risk Latino and African/American families in an urban area. The study used the Knowledge of Infant Development Inventory, a constructed measure of risky parenting practices for child well-health, home-safety, and corporal discipline, a constructed measure for children's involvement in literacy oriented activities, Edinburgh Postnatal Depression Scale, and MacArthur Communicative Development Inventories to build and test a structural equation model with AMOS/SPSS 16. The results provide support for a mediated path model. Parenting knowledge and maternal postnatal depressive symptoms interacted directly and indirectly in influencing risky parental practices and children's exposure in literacy oriented stimulation activities and emergent language. Children's involvement in stimulation activities mediated the effects of parenting and maternal mental health and directly predicted a robust amount children's emergent vocabulary. The model produced similar results for boys and girls, although boys had poorer outcomes. These findings provide empirical evidence that clinical practice and policy efforts are needed for reducing maternal postnatal depression in strengthening parenting efforts and in affording meaningful parent-child interactions and for assuring that children receive adequate exposure to activities that promote language development. Methodological limitations and recommendations for future research are addressed.