growing outrage. families of the missing are holding out hope that perhaps their loved ones are still alive. trapped in air pockets in a sunken ship. rescuers have tried to pipe oxygen into the boat. so far those efforts have been unsuccessful. the doomed ferry carrying almost 500 passengers. most high school students in a class trip when the boat began to tilt. on board a frantic battle for survival of real life heros. an extraordinary sacrifice from this young man who didn't make it off the ship. his mother hearing of his final act of generosity. his friend was crying, she says. my son gave him his life jacket. the u.s. navy is involved here. there are key elements affecting everyone. the bad weather making it so tough to see above and below the water. rescue divers have had to be rescued themselves. with every moment so critical. >> glory riviera, abc news,