On Wednesday's HLN show, Dr. Drew looked into why some mothers kill their children.

It was just a few nights ago, a mother in New York drove her minivan into the Hudson River, killing herself and three of her young children. We've seen tragic stories like this over and over. What could possibly make a mother kill her kids?

Dr, Drew discussed this with Dr. John Sharp, a psychiatrist on the faculty of Harvard Medical School, Stacy Kaiser, a psychotherapist, and CNN's Deb Feyerick who was live at the scene.