an incredible story. >> and you know what, we tracked down elliot sandler, as well. that's robert's twin brother. he has remarkable memories of what happened in those days 60 years ago. did you know throughout your life your brother's role in history? >> i had no idea until recently until the book came out. i had no idea. >> you dedicated the book to robert sandler. there's a lot of patients in your book that you told their stories. why robert in particular? >> robert was the -- was really part of the first cohort of children to be treated with chemotherapy by sidney farber in boston in 1947. and he -- he had a brief response to the drug and then relapsed. unfortunately, died soon after. but what's amazing about this story, sanjay, is that by adding more combinations of the very same kinds of drugs, eventually this disease that robert had, childhood acute lymphoplastic leukemia became curable by the mid 1970s. it was an enormous victory for pediatric cancer. it was this victory actually that propelled the idea that cancer could be curable. really was a beacon of hope