This study aimed to investigate the association between family characteristics and adherence to the EAT-Lancet dietary recommendations in 7-year-old children. This is a prospective birth cohort study with 2062 children from Generation XXI (Porto, Portugal), who provided 3-day food diaries at age 7, used to assess habitual food consumption. At the age of 4, maternal diet was assessed using a Food Frequency Questionnaire, and a diet quality score was calculated (higher scores indicating a better maternal diet), and parental-child feeding practices were assessed with the Child-Feeding Questionnaire. Adherence to the EAT-Lancet recommendations was evaluated using the World Index for Sustainability and Health (WISH) at 7, previously adapted to pediatric age. Hierarchical linear regression models (consecutive addition of blocks of variables based on a theoretical framework) were employed to evaluate the associations between family characteristics and adherence to the WISH at age 7 [β regression coefficients and the respective 95% confidence intervals (95%CI)]. Higher maternal age and education at child’s birth were associated with increased adherence to the WISH at age 7 (β=0.018, 95%CI: 0.005, 0.031; β=0.038, 95%CI: 0.024, 0.053, respectively). A better maternal diet quality, and using more restrictive practices on child’s diet, at 4 years old, were both associated with higher scoring in the WISH at 7 years old (β=0.033, 95%CI: 0.018, 0.049; β=0.067, 95%CI: 0.009, 0.125, respectively). Early maternal sociodemographic and diet quality play a significant role in influencing the adherence to a healthy and environmentally sustainable dietary pattern at school-age.