Children coughing or sneezing may be caused by infection. For example, caused by virus infection. But it does not rule out that it is related to non-infectious factors. For example, playing with some pollen or some animal hair may cause allergic cough.
Guiding opinions:
Now we can give him some experience in symptomatic treatment such as Qin Lan oral liquid. Usually you can give him more symptomatic support such as hot water.