A 4.5-year-old girl presented to the emergency department with a 5-day history of high fever, fatigue, and rash. Because of pneumonia with pleural empyema and sepsis caused by Streptococcus pyogenes, she was admitted to the pediatric intensive care unit. After initial improvement and on the eighth day, she became febrile again and also developed conjunctivitis, rash, cervical lymphadenopathy, periungual desquamation, and elevated inflammatory markers. A cardiac echo revealed a limited dilatation of the left main coronary artery. Because of suspicion of secondary Kawasaki disease, she received intravenous immunoglobulin and acetylsalicylic acid. There was an immediate clinical response with improvement of all clinical manifestations and laboratory findings. During follow-up examination 1 month later, the diameter of the left main coronary artery was within normal limits. A high index of suspicion of Kawasaki disease in children is required upon development of fever and compatible signs and symptoms in patients with serious streptococcal disease.