Children with lymph in the jaw are considered to be lymph node enlargement caused by inflammation, which may be caused by upper respiratory tract infection, acute pharyngitis, acute tonsillitis and other diseases, and may also be caused by other diseases such as gingivitis. 1. Upper respiratory tract infection: Upper respiratory tract infection is caused by viruses and other pathogens, and children will have symptoms such as cough, runny nose and fever. Upper respiratory tract infection is an inflammation of the body, which can lead to an inflammatory reaction, resulting in the appearance of lymph nodes in the jaw. 2. Acute pharyngitis: Acute pharyngitis is caused by viral, bacterial and other pathogenic infections, the main symptoms of children are dry and itchy pharynx, sore throat, fever, etc. Acute pharyngitis can also lead to inflammatory reaction of the child with enlarged lymph nodes in the jaw. 3. Acute tonsillitis: acute tonsillitis is mainly due to infection, the child will have severe sore throat, fever and other symptoms. Acute tonsillitis can also lead to an inflammatory reaction, resulting in symptoms such as enlarged lymph nodes in the jaw. 4.. Other: other diseases such as gingivitis and mouth ulcers can also cause the child to have swollen lymph nodes in the jaw. When a child has symptoms of lymph in the jaw, parents should take their child to the hospital and follow the doctor’s instructions for treatment.