June 22, 2012 (HYANNIS) A Hyannis teenager accused of playing a role in the killing of his half-brother in a dispute over their jailed father's drug business pleads guilty to being an accessory. Mykel Mendes was scheduled to go to trial Monday on a murder charge in connection with the 2009 slaying of 16-year-old Jordan Mendes. Mykel was 13 at the time. Jordan Mendes was stabbed and shot, and his body set on fire in Hyannis in December 2009. One adult -- Robert Vacher -- has been convicted in the slaying. A second juvenile-- Kevin Ribeiro -- awaits trial.