Post-discharge events, such as medication errors, can occur among pediatric patients discharged from inpatient settings to home. This prospective cohort, including infants discharged from one level 4 NICU between February 2017 and July 2019, identified a high risk for post-discharge adverse events, (including procedural complications and adverse drug events) and subsequent emergency department visits or hospital readmissions. Nearly half of these events were due to management, therapeutic, or diagnostic errors and could have been prevented.