Children with complex home care needs, such as children with cancer, are particularly vulnerable to medication errors. This longitudinal study used in-home observations and chart review to monitor 131 pediatric patients with leukemia or lymphoma for six months and found that 10% experienced adverse drug events due to medication errors in the home and 42% experienced a medication error with the potential for harm. Failures in communication was the most common contributing factor. Findings underscored a critical need for interventions to support safe medication use at home. Researchers concluded that improvements addressing communication with and among caregivers should be co-developed with families and based on human-factors engineering.