This novel tells the story of events at the Children's Mercy Hospital in Lancang County, a Lahuk Autonomous County. Three-year-old Li Zha'er has been coughing and running a fever for several days, so his mother brings him to the hospital. The pediatric outpatient department is packed. After an anxious wait, Li Zha'er is seen by his attending physician, Li Fupo. Speaking warmly in the local Lancang dialect, the doctor asks about his symptoms and then conducts a thorough examination: feeling his forehead to check his temperature, using a stethoscope to listen for lung crackles, examining his throat, checking his lymph nodes, and pressing on his abdomen. The examination shows that Li Zha'er has bronchopneumonia and needs to be hospitalized. The story follows his treatment, showing the worries he and his family face when a child falls ill, as well as the expertise and compassion of Deputy Chief Physician Li Fangcao's team and Nurse Tie Baobao. It delves into Li Zha'er's experiences during treatment, from tense moments when his condition changes to the medical staff's tireless fight against the disease, and the heartwarming scenes of his family staying by his side as he recovers. Readers will also learn about pneumonia and its treatment.