OBJECTIVE: To evaluate the experiences of families with very young children aged 1 to 7 years (inclusive) with type 1 diabetes using day-and-night hybrid closed-loop insulin delivery. METHODS: Parents/caregivers of 20 children aged 1 to 7 years with type 1 diabetes completed a closed-loop experience survey following two 3-week periods of unrestricted day-and-night hybrid closed-loop insulin therapy using Cambridge FlorenceM system at home. Benefits, limitations, and improvements of closed-loop technology were explored. RESULTS: Responders reported reduced burden of diabetes management, less time spent managing diabetes, and improved quality of sleep with closed-loop. Ninety percent of the responders felt less worried about their child's glucose control using closed-loop. Size of study devices, battery performance and connectivity issues were identified as areas for improvement. Parents/caregivers wished for more options to input information to the system such as temporary glucose targets. CONCLUSIONS: Parents/caregivers of very young children reported important quality of life benefits associated with using closed-loop, supporting adoption of this technology in this population.