Children with Kawasaki disease face a critical window where inflammatory damage to coronary arteries can create lifelong cardiovascular risks. Despite decades of standard treatment with intravenous immunoglobulin, roughly 5-10% of patients still develop coronary artery abnormalities that persist into adulthood. This randomized controlled trial tested whether adding prednisolone, a potent anti-inflammatory corticosteroid, could improve outcomes beyond current standard care. The study enrolled patients across multiple pediatric centers, comparing combined immunoglobulin-prednisolone therapy against immunoglobulin alone during the acute phase of disease. Results showed no significant reduction in coronary artery complications with the addition of corticosteroids, challenging a therapeutic approach that some clinicians had adopted based on smaller observational studies. The findings represent a definitive answer to a longstanding clinical question in pediatric cardiology. This negative result carries substantial implications for treatment protocols worldwide, as Kawasaki disease remains the leading cause of acquired heart disease in children in developed countries. The trial's robust methodology provides clear evidence against routine corticosteroid use, helping standardize care and potentially preventing unnecessary steroid exposure in thousands of young patients. For families navigating this frightening diagnosis, the research confirms that current immunoglobulin protocols remain the gold standard, while highlighting the ongoing need for novel therapeutic approaches to protect vulnerable coronary vessels during the acute inflammatory phase.