CNN Anderson Cooper 360 June 21, 2013 08:50:00
It's impossible. it happened while we were still in the woman. 3-year-old boy grayson clamp's first sound was captured on video. take a look. >> daddy loves you. daddy loves you. daddy -- >> yes. he hears. >> can you hear daddy? >> it's an incredible moment, obviously, for grayson and his family. he was born without the nerves to process sound. he is the first child to get what is called an auditory brain stem implant. a device studied in clinical trial. he had the surgery if april in north carolina. joining us is our chief medical correspondent sanjay gupta. it's remarkable to see his face li...