Purpose: To analyze the effects of children’s malocclusions and associated quality of life on family relationships by evaluating psychometric characteristics of the Family Impact Scale (FIS) in adolescents seeking orthodontic treatment. Materials and methods: Included were 334 participants (children aged 11–14 years; 53% female and 47% male) and their parents (84% mothers, 16% fathers) who were recruited at two dental clinics in Croatia. The Child Perception Questionnaire, Parental-Caregiver Perception Questionnaire, and FIS were administered. Malocclusion severity was estimated using the Index of Orthodontic Treatment Need Dental Health Component. The presence of caries was also recorded. Factor analysis, t‑test, Pearson correlation, and multiple linear regression analysis were used for statistical analysis. Results: Unidimensional FIS measuring global family impacts had higher internal consistency (α = 0.73–0.81) compared to the specific dimensions of family impacts (α = 0.60–0.69). Global family impacts were higher in children with more severe malocclusions and existing dental caries, primarily influencing parental activity, and parental emotions dimensions (p < 0.05). In multiple regression, parental perception of child’s emotional well-being, oral symptoms, and social well-being (p < 0.001) were significant predictors of global family impacts, whereas child’s quality of life perception, malocclusion severity, or child sex were not. Reduction of an increased overjet by orthodontic treatment affected changes in the global family impacts, mainly by reducing the emotional issues of parents (p < 0.05). Conclusions: The child’s malocclusion influenced the family, primarily parental emotions. Family influences were mostly determined by parental perception of the child’s altered psychosocial well-being. The FIS had adequate psychometric properties.