It is normal for an infant to make a sound when stretching. This is because when stretching, the intercostal muscles and the diaphragm in the abdominal cavity increase in tension with inspiration, and when exhaling, the diaphragm relaxes so that the airflow comes out of the throat and mouth, and sounds are made when the airflow passes through the cavity, so it is normal. If the baby has frequent stretching with sound, we should also pay attention to the possibility of children’s tics, not necessarily accompanied by stretching, will be involuntary sounds, such as dry cough or bark-like sound, there will be a brief loss of consciousness, if necessary, you can take the baby to the hospital for electroencephalography and other related tests.