Four-month-old babies are more influenced by the outside environment. The external environment includes the indoor temperature, so the windows should be opened and ventilated, which can be convective and is a good environment for cooling. Four-month-old babies can add some water between two breastfeeding sessions. If there is water, stool excretion is more fluid and sweat is guaranteed, so heat can be discharged through urination and sweating. In addition, children should not be wrapped tightly. If they wear too many clothes and cover too thickly, it is not conducive to heat dissipation. If the child does reach a fever, or even a high fever, wipe, for example, with a warm hand towel on the baby’s neck, armpits, thigh roots and other places rich in blood vessels, which are also the best places for the baby to dissipate heat. Children are prone to heat production when they eat milk and are more active, so children should not eat too much to reduce heat production.