If children have a runny nose, it is mainly due to the following reasons: 1. Firstly, children suffering from wind-heat colds will often have a stuffy nose and a runny nose after suffering from wind-heat colds. The symptoms caused by sinusitis, after the child suffers from sinusitis will also cause mucous nasal discharge, as well as often have a headache, inattention and other symptoms, you can give children timely nasal endoscopic sinus irrigation.