Expert guidance encourages interventions promoting structure-based practices to establish predictable eating environments in order to foster children's self-regulatory skills. However, few studies have examined whether and how child characteristics may moderate effects of interventions on maternal feeding practices. This analysis aimed to examine the effect of the INSIGHT Responsive Parenting (RP) intervention delivered largely during infancy, on child appetitive traits at 2.5 years and maternal feeding practices at 3 years. Primiparous mother-newborn dyads were randomized to a RP intervention designed for obesity prevention or a safety control intervention. Mothers completed the Child Eating Behavior Questionnaire at 2.5 years and the Structure and Control in Parent Feeding Questionnaire at 3 years. T-tests assessed study group differences on child appetitive traits at 2.5 years and maternal feeding practices at age 3. ANCOVA models assessed the effect of study group on parent feeding practices and tested appetitive traits as a moderator. Two hundred thirty-two mother-child dyads completed the trial. Mothers were predominantly white, non-Hispanic, college educated, and married. RP group mothers used more consistent meal routines, and less pressure, food to soothe, and food as reward compared to controls. Child satiety responsiveness moderated the RP intervention effect on maternal use of limiting exposure to unhealthy foods such that the RP intervention was most effective for children at higher levels of satiety responsiveness. Food responsiveness moderated RP intervention effects on the use of pressure-based feeding practices such that at lower levels of food responsiveness, control group mothers used more pressure than RP mothers. The INSIGHT RP intervention demonstrated sustained effects on maternal feeding practices through age 3 years, with some intervention effects showing moderation by child appetitive traits.