Toledo, Ohio (CNN) -- 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 tragedy.
Butts had worried about her son's safety when it came to street violence or driving, and she said she had always warned him of those dangers. But water accidents never crossed her mind.
"It did not occur to me that my son would drown because he didn't know water safety," she said. "Josh was never taught the basic life skill of learning how to swim."