The age of infants is relatively small, so the nasal area is not yet fully developed, and the trachea is relatively narrow compared to that of ordinary people, so it is easy to cause symptoms such as poor breathing. At night, infants’ noses may not be ventilated because the indoor environment is too dry, and indoor dryness also makes it easy for babies to get inflamed, which in turn aggravates the symptoms of nasal congestion. There is also a possibility that the nasal congestion is caused by cold and cold, and because of the weak resistance of infants, the symptoms will be more serious at night, when the nasal congestion is obvious, you can use saline to rinse the nasal cavity. Other causes are also considered to be caused by rhinitis. Consideration should be given to whether the infant is allergy-prone, and the infant should be observed to see if there are also symptoms of runny nose and sneezing. If these kinds of symptoms appear, it proves that the infant may be allergic to substances in the air, which causes nasal congestion.