Raven-Symoné is mourning her co-star Malcolm-Jamal Warner. The actor tragically died at age 54 after drowning in the ocean while on a family vacation in Costa Rica. Authorities believe he got swept up in a strong current, which also injured another man. Costa Rican National Police have announced that his cause of death was asphyxia - a condition caused by a severe lack of oxygen, per ABC News. Very, very sad. Related: Sharon Osbourne Reacts To Heartfelt Ozzy Tribute After His Death Malcolm and Raven-Symoné met on the set of The Cosby Show.