Malcolm-Jamal Warner, the actor, who has died aged 54, was cast as Theo Huxtable in the sitcom The Cosby Show at the age of 13, and over the course of some 200 episodes became one of US television’s best-known teenagers.

Mr. Warner, who played the only son of Bill Cosby’s character on the beloved 1980s sitcom, drowned in Costa Rica.

Malcolm-Jamal Warner suffered a devastating personal heartbreak with the death of his girlfriend years before he became a husband and father. The beloved Cosby Show star was at the bedside of his former girlfriend, Michelle Thomas, when she died from cancer in 1998. Warner dated Thomas, who ...