Actor Malcolm-Jamal Warner, who starred in The Cosby Show, has died. He drowned while swimming on vacation with his family in Costa Rica. He was 54 years old.

Warner starred in The Cosby Show as Theo Huxtable, the only son (there were four daughters) of obstetrician Cliff Huxtable and lawyer Clair Huxtable. He was a main star in nearly all eight seasons of the show, with recurring episodes in some seasons while his character was in college.

He was born on August 18, 1970, in Jersey City, New Jersey, and started acting when he was still a child. Warner graduated from The Professional Children’s School in New York City, and made his onscreen debut in an episode of Matt Houston in 1982. While he was starring in The Cosby Show, Warner appeared in CBS Storybreak, Matlock, A Different World, and The Fresh Prince of Bel-Air.

Warner was in The Tuskegee Airmen TV movie and voiced the Producer in The Magic School Bus. He starred in the buddy sitcom Malcom & Eddie with Eddie Griffin from 1996 to 2000. He voiced Lester Biggs in an episode of Static Shock, starred in the TV series Jeremiah and Listen Up, and was in an episode of Dexter.

He was in Fool’s Gold, and did episodes of Community, Sons of Anarchy, Key and Peele, and American Horror Story. Warner starred in Reed Between the Lines, had a recurring role in Major Crimes, was in episodes of Suits, and played A.J. Austin in The Resident. His last role was starring in episodes of Alert: Missing Persons Unit.