“The Cosby Show” alum Keshia Knight Pulliam paid tribute to her former co-star Malcolm-Jamal Warner after his death at age 54 with a touching social media post on Sunday. Knight Pulliam, 46, shared an Instagram video of Warner playing bass guitar onstage for a live audience at City Winery in Atlanta.

The beloved actor died at 54 while on vacation with his family in Costa Rica. Learn more about his sudden passing and cause of death here.

Malcolm-Jamal Warner's cause of death has been released by police. The actor, who is best known for his role as Theo Huxtable in the hit TV sitcom "The Cosby Show," died on Sunday off the coast of Costa Rica after a drowning, Costa Rican National Police told ABC News. He was 54.

The actor's friends, colleagues and fans got together for a special livestream episode of 'Not All Hood,' the podcast he co-hosted with Candace KelleyMalcolm-Jamal Warner may be gone, but he's certainly not forgotten.

Malcolm-Jamal Warner tragically drowned in Costa Rica, with new details confirming the status of a second victim involved in the incident