A St. Louis teenager is being praised as a hero for helping four relatives escape from an arson fire that had blocked the front and the back doors of their home. The 84-year old great-grandmother of Demelle Johnson says he’s the only reason she, her sister, her daughter and her sister’s daughter are alive. All of them were asleep when the house was set on fire. Police say the boy, who is 16, got to the house just as a family relative was setting the fire. He woke everybody up and got them out a window, which was their only means of escape. Two of the women have been hospitalized. One is critical because of smoke inhalation. Police have arrested the man suspected of setting the fire.