The normal temperature range for a 1-month-old baby is 36-37.4°C, but most babies often have a temperature range of 36.2-37.2°C. If it exceeds 37.5°C, it is a fever. This temperature change is related to two aspects, the first is the time, generally speaking, the temperature is high between afternoon and evening, and there is a period of time when the temperature is low, that is, from midnight to early morning. The second is related to movement and activity. If the baby has just finished breastfeeding, especially if it is held in the mother’s arms, his body temperature will be high. A common situation is that the child cries, and if after a period of crying, his temperature will also be high, but none of it will exceed 37.5°C.