Every child is a mystery, but as scientific advances in prenatal testing grow, so does the temptation to know more and more about our unborn children. Will they be healthy? What are the chances they will have a disability? With questions like these comes another question: how much is too much when it comes to trying to know who our children will be? My guest is Dr. Mary O’Callaghan, a developmental psychologist who, among other things, studies, writes about, and teaches on “disability selective abortion” and issues of human dignity.