A four-year-old baby with a fever of 39°C should be given immediate oral antipyretic medication, such as ibuprofen and acetaminophen, in appropriate doses orally according to the baby’s weight. At the same time, reduce the clothes worn by the baby so that the baby is in a cool, comfortable and ventilated environment. Give your baby plenty of water to avoid dehydration due to fever. If your baby has cold hands and feet with chills during fever, you can soak your hands and feet in warm water. If your baby is in good spirits, with warm hands and feet and no chills, you can use ice packs or ice cubes to apply cold compresses to your baby’s head. Take your baby to the hospital promptly and ask the doctor to help you find the cause of the fever and treat it effectively. If you have fever patches at home, you can also put them on your baby’s forehead to help reduce fever.