The main goal of this paper is to examine how parental attitudes toward sleeping, screen use, and feeding their child influence the child’s body mass index (BMI) through the child’s behaviors related to time dedicated to sleep and television, and their healthy eating. Using survey data from 908 parents, results show that parental attitudes have a significant influence on children’s behavior and, more importantly, on their BMI. The three forms of a child’s behavior (sleeping, watching TV, and healthy eating patterns) are affected by what parents do and their attitudes toward these three behaviors at home. Results show how changes in parental attitudes are an interesting target to prevent the child’s overweight.