Prolonged critical illness in children has emotional consequences for both parents and providers. In this observational cohort study, we longitudinally surveyed anxiety and depression in parents and moral distress in pediatric intensive care unit (PICU) providers (attendings, fellows, and bedside registered nurses) and explored their trajectories and relationships. Anxiety/depression and provider moral distress were measured using the Hospital Anxiety and Depression Scale and the Moral Distress Thermometer, respectively. The relationships of parental and provider distress were evaluated using Spearman's correlations, and their trajectories and potentially associated variables were explored using quadratic random slope and intercept models. Predetermined associated factors included demographic and clinical factors, including parent psychosocial risk and intubation status. We found parental anxiety and depression decreased over their child's admission, and parental psychosocial risk was significantly associated with anxiety (coefficient = 4.43, p < 0.001). Clinicians in different roles had different mean levels and trajectories of moral distress, with fellows reporting greater distress early in admissions and nurses later in admissions. Parental anxiety/depression and provider distress were significantly, though moderately, correlated. We conclude that anxiety and depression in parents of children with prolonged PICU admissions and the moral distress of their clinicians correlate and vary over time and by provider role.