From CNN.com, by Lan Trinh: Wanda Butts dropped the phone and screamed when she heard the news that her son was dead. Josh had drowned while rafting on a lake with friends. The 16-year-old didn't know how to swim, and he wasn't wearing a life jacket. "I couldn't believe it, I didn't want to believe it: that just like that, my son had drowned and he was gone," she said, recalling the 2006 trage…