Malcolm-Jamal Warner, the actor and musician who rose to fame as a teenager playing Theo Huxtable on NBC’s groundbreaking sitcom “The Cosby Show,” has died at the age of 54.

Warner reportedly drowned on Sunday while swimming near Limón on the Caribbean coast of Costa Rica, according to the country’s Judicial Investigation Department. Authorities said he appeared to have been caught in a strong current. Bystanders attempted to rescue him but were unsuccessful. The beach is known as a popular destination for surfers.

Mr. Warner was just 14 years old when he catapulted to stardom, portraying Theo, the only son of Heathcliff and Clair Huxtable, played by Bill Cosby and Phylicia Rashad, in what became one of television’s most iconic families.

“The Cosby Show” aired from 1984 to 1992, consistently topping ratings and breaking barriers for Black representation on television.

The success of “The Cosby Show” turned Warner and his castmates into household names. But he was far from a one-role actor. Over the decades, Warner built a rich and diverse career. He starred alongside Eddie Griffin in the hit UPN sitcom “Malcolm & Eddie,” which ran for four seasons beginning in 1996.

In 2011 he took on the role of a modern-day TV dad in BET’s “Reed Between the Lines,” acting opposite Tracee Ellis Ross. Warner also had recurring roles on several acclaimed shows, including “The Magic School Bus” and nearly 100 episodes of Fox’s “The Resident,” in which he played Dr. AJ Austin. In 2016 he portrayed A.C. Cowlings in “American Crime Story: The People v. O.J. Simpson,” part of Ryan Murphy’s Emmy-winning anthology series.

In addition to acting, Warner was a multitalented artist. He directed several episodic television shows, performed on stage, wrote poetry and played bass guitar. His musical talent earned him a Grammy Award in 2015 for Best Traditional R&B Performance, shared with Robert Glasper and Lalah Hathaway for the song “Jesus Children of America.” Two years ago, he received a Grammy nomination for best spoken-word poetry album, for “Hiding in Plain View.” I ran into Warner backstage at the Grammys that year, and we chatted up about how much he loved being in the world of music.

Malcolm-Jamal Warner was born on August 18, 1970, in Jersey City, N.J. When he was five years old, his family moved to Los Angeles. He began acting as an after-school activity and soon found himself on a national stage.

In an interview with Backstage, Warner recounted how his initial audition for Theo Huxtable didn’t go as planned; he played the character with exaggerated sass and eyerolls. Cosby rejected the performance, “I thought I had blown it, but I worked on the scene with my acting teacher,” Warner recalled. “This time when I auditioned, it was real. Mr. Cosby’s philosophy is that all humor is based on truth.”

That truth became the foundation of Warner’s enduring success, much of which can be attributed to his mother, Pamela Warner. A fierce advocate and guiding force, she helped him navigate the unpredictable terrain of child stardom with care, discipline and wisdom. In an industry where early fame can derail young lives, Pamela Warner helped her son build a long, multifaceted career grounded in integrity. Most recently, she shared her hard-earned insights in her book, “A Parent’s Guide to Managing Showbiz Kids,” which has become an essential resource for families raising children in entertainment.

Warner often spoke about the powerful women in his life: his mother, his wife and his daughter. In fact, he did so just days before his death, on the latest episode of his podcast, “Not All Hood,” a thoughtful, personal series exploring the Black experience, fatherhood and cultural resilience.

In that final episode, he reflected on the continuing challenges Black people face in society: “So everything that we have to muster — all of our resources, whether it be spiritual, whether it be relational, whether it be political to whatever extent — everything that we have had to muster just to play on this playing field is what makes us rich as Black people, as Black culture.”

His last post on Instagram has since taken on a bittersweet resonance. In a short video message, Warner shared a moment of encouragement and light: “I want to remind you as I remind myself that no matter what’s going on, there’s always a reason to smile. If you just take a minute to stop and take stock, I guarantee you can find that one reason to smile. And if for some reason you can’t find a reason to smile, then that’s why it’s the best time to be the reason for somebody else. So that’s more for yourself and be a reason for someone else. Peace and love and I’ll be back soon.”

I’ve watched that video several times, and it still brings a smile to my face. Thank you, Malcolm-Jamal Warner, for keeping us smiling for so many years with your humor, your humanity and your heart. Malcolm Jamal-Warner is survived by family, friends and generations of fans who grew up with Theo Huxtable and continued to follow his dynamic work across genres and mediums.