Malcolm-Jamal Warner, the actor perhaps best known for starring in the TV sitcom "The Cosby Show" as son Theodore "Theo" Huxtable, has died at 54. Warner drowned off the coast of Costa Rica on Sunday, Costa Rican National Police told ABC News. Warner's official cause of death was asphyxia, police said.

Malcolm-Jamal Warner was notoriously private about his personal life in recent years, but that wasn’t always the case. The actor, who tragically died from an accidental drowning during a family vacation to Costa Rica on July 20, had several high-profile romances with actress girlfriends before settling down to become a family man.

The second person involved in Malcolm-Jamal Warner's drowning death remains in critical condition but new information has emerged about why they were in the water with the actor, PEOPLE can exclusively confirm.