Jeffrey Carlson, a stage and screen actor best known for a historic turn as a transgender character on the daytime soap opera “All My Children,” has died. He was 48.

The Cook County Medical Examiner’s Office confirmed Carlson’s July 6 death to People on Sunday, but did not announce the cause.

Among those to express their condolences was fellow actor Susan Hart.

“For those of you that don’t know, I’m very sorry to share the news that Jeffrey passed away yesterday,” Hart wrote in a July 7 Facebook post. “I have been respectful of his family’s privacy in not sharing the news sooner … also could not breathe or function … still can’t … love to all … just devastated .. ”

Other friends, actors and former collaborators shared their memories of Carlson on social media.

“A powerful actor and a painful loss,” Adam Feldman, theater critic for Time Out New York, wrote on Twitter. “I first saw him in a Lee Blessing play called Thief River when he was still in Juilliard and it was clear he was something special.”

“Jeffrey gave beautiful and nuanced performances during a career which took him from television and film to Broadway and, fortunately for us, to STC,” the Shakespeare Theatre Company of Washington, D.C., wrote on Instagram. “We send our love to Jeffrey’s friends, family, and colleagues, those who knew and loved him dearest.”

Jeffrey Carlson at the 2007 GLAAD Media Awards in New York.
Jeffrey Carlson at the 2007 GLAAD Media Awards in New York.

Bryan Bedder via Getty Images

A Long Beach, California native, Carlson attended the University of California at Davis before graduating from New York’s Juilliard School in 2001.

He made his Broadway debut in 2002, starring opposite Bill Pullman in the Tony-winning play “The Goat, or Who Is Sylvia?” He also appeared in the 2003 Broadway revival of “Tartuffe,” and gave a memorable performance in the short-lived Boy George musical “Taboo” that same year.

His breakout role, however, came in 2006 when he joined the cast of “All My Children” as a rock musician named Zoe who was later revealed to be transgender. It reportedly marked the first transgender character on daytime television, winning “All My Children” a GLAAD Award in 2007.

“I was very moved by it,” Carlson told the Los Angeles Times in 2006 about learning of the character’s journey toward living as their authentic self. “If it creates a conversation, I think we’ve done our job.”

He reiterated that stance in a 2007 interview with People, noting: “We’re not doing this for shock value. The goal is to cause a conversation — and that’s happening.”