Introduction Fever in infants under 3 months of age is considered a medical emergency. Unlike older children and adults, young infants have immature immune systems and may not show typical signs of illness. Even a mild temperature elevation in this age group can indicate a serious bacterial or viral infection, such as sepsis, urinary tract infection, or meningitis. Prompt medical evaluation is essential to prevent complications, identify the underlying cause, and initiate timely treatment. Understanding Fever in Young Infants Causes of Fever in Infants Under 3 Months Fever may indicate serious or minor conditions, but all cases should be evaluated…