Measurement of COVID-19 severity in children is key to determine the implications associated with the pandemic. The results of this study highlighted the importance of considering different age groups when assessing disease severity in COVID-19. ISARIC4C further observed that results were consistent when data were restricted to unvaccinated children. To gain insight, the ISARIC4C team obtained data from hospitalised children across different age groups and countries. The severity of disease was assessed by admission to Intensive Care Units, the need for ventilator support or oxygen therapy. The different implications of the severity among the children is possibly attributable to the multiple SARS-CoV-2 variants emerging over the COVID-19 pandemic.