Parent emotion socialization refers to the process by which parents impart their values and beliefs about emotion expressivity to their children. Parent emotion socialization requires attention as a construct that develops in its own right. The socialization of child worry, in particular, has implications for children's typical socioemotional development, as well as their maladaptive development towards anxiety outcomes. Existing theories on emotion socialization, anxiety, and parent-child relationships guided our investigation of both maternal anxiety and toddler inhibited temperament as predictors of change in mothers' unsupportive (i.e., distress, punitive, and minimizing) responses to toddler worry across 1 year of toddlerhood. Participants included 139 mother-toddler dyads. Mothers reported on their own anxiety and their emotion socialization responses to toddler worry. We assessed toddler inhibited temperament through a mother-report survey of shyness and observational coding of dysregulated fear. Maternal anxiety but not child inhibited temperament predicted distress reactions and punitive responses, whereas maternal anxiety and toddler dysregulated fear both uniquely predicted minimizing responses. These results support continued investigation of worry socialization as a developmental outcome of both parent and child characteristics.