The mystery of who killed a New Jersey family of four, setting their Colts Neck mansion aflame, may have been solved. Prosecutors say they believe 51-year-old Paul Caneiro shot his brother and business partner, Keith, repeatedly in the early hours of November. 20. He then allegedly turned his attention to Keith's wife, Jennifer, and their children, Sophia, 8, and Jesse, 11, stabbing them repeatedly. Investigators say Paul set a fire in their basement to destroy evidence.