Runny nose is a secretion produced by the nasal cavity, and most people produce runny nose. However, parents must pay attention if the nasal discharge produced by babies appears abnormally sticky. Parents must find out the cause and treat it properly, because children’s cold, chronic rhinitis, sinusitis, nasal polyp infection and atrophic rhinitis can all lead to thickened nasal discharge. Runny nose is a common manifestation of nasal diseases. The nasal discharge is mainly through the anterior nostril, but it can also flow back to the nasopharynx. Generally, there is a small amount of mucus inside the baby’s nasal cavity, mainly to keep the nasal cavity moist, but when there is a lesion in the nasal cavity, the nature and amount of nasal mucus will change to a certain extent. If your child’s nasal discharge is serious or sticky, it is best to take your child to the hospital for examination to see what causes it, and then carry out symptomatic treatment to avoid delaying your child’s condition.