A fever with blisters in the baby’s mouth should be caused by a viral infection, wind-heat cold, or heat toxicity in the body. It may also be caused by diseases such as hand, foot and mouth disease. It can be treated with antipyretic and antiviral drugs. You can take Yi Qing Oral Liquid, Qing Kai Ling Oral Liquid, Compound Jin Yin Hua Granules, Ribavirin Granules for treatment. Pay attention to oral care, rinse your child’s mouth with salt water more often, keep a light diet, and spray watermelon cream spray in the mouth to relieve the blistering situation. The diet should pay attention to eating more cool fruits, such as Sydney, Luo Han Guo, grapefruit, apples, strawberries, etc. Eat more bitter melon and drink more mung bean soup, which can also play a role in clearing heat and detoxification. Pay attention to emotional relaxation, do not overstress. The indoor air should not be overly stuffy, and you also need to pay attention to washing your hands regularly to keep them clean and hygienic so that your child does not get sick from the mouth.