7-year-old child lymph node swelling may be acute upper respiratory tract infection, sepsis, purulent tonsillitis and other causes. 1. Acute upper respiratory tract infection: epidemic viruses invade the human body, leading to a reduction in the local defense function of the respiratory tract, pharyngitis-based upper respiratory tract infection clinical manifestations of the pharynx is obviously congested edema, submandibular lymph node swelling and pain. 2. Septicemia: due to the child’s low immunity, external bacteria invade the human body, causing bacterial infection. Clinical manifestations are fever, headache, swollen lymph nodes and other symptoms. 3. Purulent tonsillitis: bacteria accumulate in the tonsil fossa, when the body resistance is lowered, tonsillitis is induced, mostly seen in children and teenagers. Symptoms include fever, throat discomfort, and enlarged lymph nodes in the neck. Enlarged lymph nodes are often accompanied by other diseases, if you find that your child’s lymph nodes are enlarged, you should consult a doctor in time to avoid delaying the condition.