Despite the increasing number of studies on the health-related quality of life (HRQOL) of children with type 1 diabetes (T1D), little is known about the influence of family and parental factors on this outcome. This study aimed to explore whether family cohesion and children’s HRQOL were connected through three indicators of parental psychological adjustment (parenting stress, depressive symptoms, and anxious symptoms) as well as whether these links varied according to the child’s age. Levels of family cohesion, parenting stress, and depression/anxiety symptoms of parents of children with T1D and parents of healthy children were compared. The sample included 88 child-parent dyads composed of children/adolescents (8-18 years old) with T1D and one of their parents and 121 dyads composed of healthy children/adolescents and one of their parents. The parentscompleted self-report measures of family cohesion, parental stress, and emotional adjustment, and the children completed measures of HRQOL. Testing of the hypothesized moderatedmediational model showed that higher HRQOL ratings in children were associated with higher levels of cohesion through lower levels of parental stress, regardless of the child’s age.Parents of children with T1D perceived less cohesion and felt more anxiety and stress about parenting tasks compared to parents of healthy children. Our findings suggest that parents of children with T1D are at an increased risk of psychological maladjustment. Moreover, this study highlights the interrelation between family/parental functioning and child adjustment and makes an innovative contribution by identifying a mechanism that may account for the link between family and child variables