Robert Cotter, 18, was arrested Friday and charged with murder after allegedly confessing to shooting both his father and his brother. Authorities discovered Patrick Cotter, 53, dead from a gunshot wound in his mobile home in Fresno on May 17. Brian Cotter, 15, was found alive, but suffering a gunshot wound. Robert was in the home at the time, unharmed. During an interrogation, he said Brian had shot their father and then himself. Brian died at a nearby hospital days later undergoing treatment for his wounds. Police arrested Robert after finding his story inconsistent with evidence gathered from the scene. They say that he confessed during questioning.