There are many reasons for a two and a half year old child to have a sudden onset of fever, and it needs to be treated according to the specific cause and the temperature of the fever, which includes medication, physical cooling therapy, and so on. The reason for this is the fact that it is not a good idea to have a good time, but it is a good idea to have a good time, and it is a good idea to have a good time. First of all, you need to observe the temperature of the child’s fever, if the temperature of the child’s fever is measured at 38.5 degrees or more, you need to follow the doctor’s instructions to give antipyretic treatment. For example, ibuprofen and acetaminophen. Physical cooling: If the child’s measured temperature is below 38.5 degrees, and there is no cough, headache, diarrhea and other discomforts, you can use physical cooling methods to reduce fever, for example, you can give the child to drink some warm boiled water, open the window to ventilate the room, or use the head of the antipyretic patch, to achieve the effect of lowering the temperature. In addition, you need to pay extra attention to the child in addition to fever, there is no accompanying other symptoms of discomfort, such as headache, cough, poor mental health. If accompanied by other uncomfortable symptoms, must promptly go to the regular hospital for medical treatment, in order to clarify the cause of the disease, timely and appropriate treatment.