Seasonal changes can profoundly affect children's mental health, especially in winter as days become shorter and it gets too cold to play outside. Pediatrician Cindy Gellner, MD, explains how seasonal affective disorder (SAD) can impact children, causing significant changes in their mood and behavior. Learn the biological underpinnings of SAD, its effects on serotonin and melatonin levels, and various treatment strategies from natural light exposure to clinical interventions.