It is common for children to have a cough that does not occur during the day but is strong at night because there are many reasons that can aggravate the symptoms of coughing at night. During the night, if children open their mouths to breathe during sleep because of nasal congestion and other reasons, dry air enters the respiratory tract directly through the mouth without being moistened by the nasal cavity, which can easily lead to dryness of the respiratory mucosa, thus triggering the aggravation of coughing. Drinking more water or using a humidifier in the house is more effective, and using saline to nebulize inhalation therapy before going to bed can also moisten the airway. Another reason is that at night, the child’s vagus nerve tends to become excited, leading to spasm of the bronchial smooth muscle, which can trigger a cough, so the cough is stronger at night. In addition, if the child has a cough caused by dust mite allergy, he or she is more exposed to dust mites inside the blanket during sleep at night, which makes the cough worse.