Some children have a certain time pattern of coughing, not during the day but at night. If the child is very cheerful and not wilting or very uncomfortable, consider whether the child has a problem called upper airway cough syndrome. This problem can be caused by inflammation of the upper airway, such as postnasal drip, or a cough that is triggered by an upper respiratory tract infection that may occur more easily at night. Other children may sleep at night in an environment where there are allergic substances, called allergens, and they may not cough during the day and then start coughing again at night when they return to their bed. Other children may have a cough at night because they are not fully digested when they lie down, or they have poor digestion, which can cause GERD. It is also entirely possible that some children are actually not noticed by us parents because parents are at work during the day and the child may be sent to kindergarten thinking that he does not have a cough, but in fact he may not get enough attention from us during the day. In conclusion, this regular cough in small children can still provide a lot of help in the analysis of the etiology, and it is very good for parents to be able to observe it.