After a child receives the Hepatitis B vaccine, a low fever reaction may occur. Parents should not be overly anxious. Generally, a body temperature below 37 degrees is normal. If it exceeds 37 degrees, it is appropriate to give more water and milk. If the fever exceeds 38 degrees, fever-reducing measures should be taken. For the causes of pediatric liver disease, parents should cooperate with the doctor for treatment and pay attention to their child’s dietary habits.