Los Angeles, California - Actor Jeffery Carlson, known for his groundbreaking role as transgender character Zoe onthe TV show All My Children, passed away at the age of just 48.

Actor Susan Hart, who shared the stage with Carlson in several plays, broke the news of his death on Facebook.

"For those of you that don’t know, I'm very sorry to share the news that Jeffrey passed away yesterday," she wrote on July 7. "I have been respectful of his family’s privacy in not sharing the news sooner."

Carlson appeared on Broadway, TV, and the 2005 movie Hitch.

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But he was best known for starring in 59 episodes of the famous soap opera, All My Children. The show made TV history when it introduced the first transgender role to daytime TV in 2006. Carlson's groundbreaking character was initially a British rock star named Zarf, who later returned as Zoe.

The show dove into Zoe's transition, including her medical visits and coming out. Carlson told People Magazine in 2007, that Zoe's story was "meant to cause a conversation."

"Members of the transgender community are talking with the regular posters on the All My Children chat rooms," he said. "I got a letter from an 11-year-old girl. It said, 'It’s cool you’re going to become a girl. Then we will have stuff in common.'"

As news of Jeffery's death spread friends and colleagues posted Tributes on social media.

Time Out New York theater editor Adam Feldman tweeted: "A powerful actor and a painful loss. It was clear he was something special."

The Shakespeare Theater Company wrote on Facebook: "STC is saddened to learn of the recent passing of Jeffrey Carlson. Jeffrey gave beautiful and nuanced performances during a career."

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Carlson's All My Children co-star Eden Riegel also chimed in, tweeting: "I feel fortunate to have called this kind soul a friend and see his brilliant work up close. Gone far too soon – an unimaginable loss. Love you, Jeffrey. Rest friend."

The cause of Carlson's death has not yet been made public.