Your baby has a cold and has a bad cough at night. Usually by this time of night, it is not possible to have a particularly specific indication, it depends on the exact degree of cough and whether it is accompanied by other symptoms of coughing up sputum. If the cough lasts for a long time, it is likely to cause inflammation of the bronchial tubes, and in severe cases, the baby may have pneumonia. Therefore, if the cough is severe, a relevant examination can be performed, starting with an auscultation of the lungs, followed by a chest X-ray or CT of the chest to clarify the severity of the pneumonia. If there is only bronchitis, symptomatic cough suppressants can be applied, and if there is pneumonia, appropriate treatment should be done. Other coughs are caused by specific pathogens, such as Mycoplasma pneumoniae or even Mycobacterium pertussis. In this case, the relevant tests should be performed to identify the pathogen and antibiotics or other causative medications should be applied according to the pathogen.