Background: Children who become critically ill and require Pediatric Intensive Care Unit (PICU) hospitalization may develop negative psychological outcomes following discharge. Despite this concern, there have been no systematic attempts to intervene with critically ill children to promote well-being, and prevent long term sequelae. The aim of this pilot study is to test the feasibility and acceptability of a PICU nursing intervention that seeks to enhance child comfort and promote sleep quality and duration in the PICU, potentially promoting psychological well-being post-discharge. The intervention is based on principles of Developmental Care, a philosophy of care that includes the child and family, and incorporates intervention strategies to reduce environmental stressors and improve quality of life. In view of the critically ill child's state of physical and emotional vulnerability, and the highly noxious environmental stimuli they are exposed to in the PICU, our proposed intervention has the potential to enhance physiological and psychological stability in this population. We will examine intervention effects on children's quality of sleep and sleep duration in the PICU, psychological distress post-PICU, and on parent anxiety during and following their child's PICU hospitalization.