Babies are not only different from adults, but also different from older children. Hearing a small baby coughing up phlegm but not coughing it up is a thing that makes adults very anxious and “unable to use their strength”. There are several ways to deal with this phenomenon. First, the infant’s respiratory muscle strength is relatively weak, can be patted on the back, prompting phlegm in the airway to move, stimulate the child to cough, cough out the phlegm. For bedridden babies, you can switch positions back and forth so that one side of the body is on top, which is also conducive to the drainage of phlegm. In addition, you can give your child some medication to promote the dilution of phlegm, phlegm thinning, naturally easy to cough out. The room can be kept moist, also helps to avoid the respiratory tract is too dry. Often, when you hear phlegm but can’t cough it up, it may be because the phlegm is “too deep”, so you may need to use some bronchodilator drugs, such as nebulizer. On the other hand, if the phlegm is caused by inflammation of the bronchial tubes or lungs, then there is no effective symptomatic anti-infective treatment, even if the phlegm is coughed up, there will be a next time, after effective control of the infection, a lot of “phlegm” will be gone. Therefore, small infants with phlegm must be targeted to find the cause, and then integrated symptomatic care and treatment.