Bill Cosby is mourning the loss of his on-screen son Malcolm-Jamal Warner. "This reminds me of the call I got when I was taping The Cosby Show and I got a call saying that my son, Ennis, had been murdered," Cosby, 88, told Us Weekly via his rep, Andrew Wyatt, on Monday, July 21. "It's just devastating." Cosby's son Ennis died in 1997 in a failed robbery attempt at the age of 27, while he and Warner costarred as Cliff and Theo Huxtable on The Cosby Show from 1984 to 1992. (In addition to Ennis, Cosby shares kids Erika, Erinn, Ensa and Evin with wife Camille.