Familial chylomicronemia is caused by deficiency of lipoprotein lipase or its co-activators. Here, we report an infant with apolipoprotein C-II (APOC2) deficiency, who developed acute pancreatitis 37 days after birth. He presented as abdominal sepsis with fever, irritability and abdominal distention. Amylase levels were low, but lipase levels and imaging findings were consistent with acute pancreatitis. He had severe hypertriglyceridemia (1091 mg/dl). Keeping him nil orally for two days resulted in rapid decrease in triglyceride levels and resolution of the clinical findings. APOC2 gene sequencing revealed a homozygous splice-site mutation (c.55 + 1G > C). To the best of our knowledge, this patient is not only the youngest reported patient with APOC2 deficiency, but also the youngest such patient who developed pancreatitis. Although he had a severe presentation, invasive methods to treat hypertriglyceridemia were not necessary. We emphasize that clinical findings and amylase levels are not reliable to diagnose pancreatitis in this age group. (C) 2020 IAP and EPC. Published by Elsevier B.V. All rights reserved.