Pertussis without a crowing sound indicates recovery. Pertussis, also known as whooping cough, is an acute respiratory infection caused by Bordetella pertussis, commonly seen in children. The progression of pertussis can be divided into three stages: The first stage is the catarrhal stage, also known as the pre-paroxysmal stage. At the early stage, the child shows symptoms similar to the common cold, followed by worsening cough. If the condition is not effectively controlled during this stage, It then progresses to the second stage, the paroxysmal stage. During the paroxysmal stage, the child exhibits characteristic episodic spasmodic coughing and crowing inhalation sounds. This period can last up to two months. Finally, it moves into the recovery stage. In the recovery stage, the frequency and severity of the episodic spasmodic cough and crowing inhalation sounds gradually alleviate. Thus, the absence of a crowing sound in whooping cough is an indication of approaching recovery.