Three months baby cough with phlegm, most because of colds caused by respiratory infections, can be upper respiratory tract infections, but also may be for the lower respiratory tract infections such as acute bronchitis, pneumonia, need to symptomatic treatment. If the cough just started, not too serious, no high fever symptoms, you can temporarily do not have to take medication, every day to give the child more boiled water, pay attention to let the baby more rest, try to hold the child out of the sun as much as possible, can promote the absorption of calcium, enhance the body’s immunity, to resist the disease is very favorable, most of the week or so can be self-cured. Can also be appropriate to give the child to take cough medication, symptomatic treatment. If the baby has a cough with phlegm, accompanied by nasal congestion, runny nose, or coughing for 2-3 days without relief, considered to be the feeling of external evil caused by upper respiratory tract infection symptoms, you can take some drugs for colds. If there is a fever, and the cough is more serious, it is best to take the child to the hospital in a timely manner, to do the relevant examination, pay attention to the possibility of bronchitis, pneumonia, timely symptomatic drug treatment, to avoid delaying the condition. Small infants have a cold, cough and other symptoms, if the symptoms are not too serious, the child’s immune function is normal, there is a possibility of self-healing. If the cough is not relieved or aggravated, it is necessary to consult a doctor in time for treatment.