This study tested feasibility of a developmentally sensitive adaptation of a behaviorally based group parent-training intervention designed to improve adherence to cystic fibrosis nutrition recommendations and address a variety of mealtime behavior management problems. Modifications to the original intervention are described. Parents of 4 children ages 21 to 31 months with cystic fibrosis participated. Two children were malnourished and had primary goals of increasing intake and weight; 2 were adequately nourished and had primary goals of improving diet quality. Additional data are provided for 1 child regarding child disruptive behavior. Anthropometric data were collected at baseline, pre- and posttreatment, and follow-up and retrospectively via chart review. Families completed 3-day diet diaries across 2 baseline weeks, 6 weeks of intervention, and at a 12-week postintervention follow-up. Data support acceptability of this intervention to parent participants. The 2 malnourished children increased caloric intake throughout the intervention and demonstrated clinically significant weight gains at posttreatment. Furthermore, these gains were maintained at follow-up. One of the 2 adequately nourished children demonstrated improved diet quality. Findings provide some support for the feasibility for parent group intervention providing training in cystic fibrosis-specific child behavior management skills to multiple families. Preliminary results suggest that this intervention may provide benefits to parents who often struggle with the demands of nutrition requirements and toddler behavior.