Background: Parents are increasingly pursuing weight loss in medical weight management programs, yet little is known about the presenting behaviors and practices of children who have parents initiating these programs.Objective: To describe congruence in weight control practices, sedentary and screen time behaviors, and family functioning and communication between parents initiating a medical weight management program and their children (ages 7-18). Methods: Twenty-three dyads were enrolled and had measured height/weight and research packets completed including perceived weight status, weight control practices, sedentary and screen-time behaviors, and family functioning and communication. Paired t-tests and intraclass correlations assessed congruence; independent t-tests determined differences based on child demographics (age, sex, and weight status). Results: Parents underestimated children's use of weight control practices compared to child reports. Children with overweight, males, and older in age had increased weight control practices and sedentary and screen-time behaviors. Children who perceived themselves to have overweight reported more impaired family communication than children perceived to be a healthy weight. Conclusions: This study highlights the discrepancy between dyads' reports of children's behaviors, and identifies that specific child populations with overweight, older in age, and males are at-risk of experiencing less healthy behaviors and impaired family communication. Future research should monitor changes over time in parental weight management programs to determine effects based on parental weight loss.