Background: Familial hyperinsulinemia is the most common cause of persistent hypoglycemia in infancy and is due to defective negative feedback regulation of insulin secretion by low glucose level. It is also referred as Congenital Hyperinsulinism, Nesidioblastosis or Persistent hyperinsuinemic Hypoglycemia of Infancy. Characteristics: A 2 day old baby with recurrent (persistent) and severe hypoglycemia along with g6pd variant Outcome Baby diagnosed to have hyperinsulenemic hypoglycemia on Next generation sequencing later on started on inj octrotide on which she improved and got discharged in stable condition. Message: The condition should be considered in the differential diagnosis of severe and persistent hypoglycemia in neonates.