Michelle Trachtenberg Had 'Pulled Back from Hollywood' and Was Reclusive Before Her Sudden Death (Exclusive Source)

Michelle Trachtenberg had been living quietly and under the radar before her sudden death at 39.

Trachtenberg was found dead in New York City on Wednesday, Feb. 26. The New York City Medical Examiner's Office confirmed to PEOPLE on Feb. 27 that the actress' family objected to an autopsy, meaning that her cause of death would be ruled "undetermined."

While Trachtenberg made a name for herself early on, with roles across television and film, a friend of hers exclusively tells PEOPLE the Gossip Girl alum had taken "a step away from Hollywood" in recent years.

"She just had the story of childhood stardom. She had a couple roles throughout the last decade, but nothing of real note," the source says of Trachtenberg, whose last credited role was in 2023, reprising Georgina Sparks on Max's Gossip Girl reboot.

"She really pulled back from Hollywood [in] the last eight years," the source notes. "She was a great girl who just never got her footing, just like many childhood stars."

Michelle Trachtenberg at the Cadillac Celebrates the 92nd Annual Academy Awards event on Feb. 6, 2020.

JC Olivera/WireImage

While navigating the next steps in her career, the Buffy the Vampire Slayer alum "was a recluse [and] didn't have many friends," according to the source.

Still, the friend notes, "She was an overall great girl. She was always kind, supportive and loving."

"It's so sad. It really is. She was an amazing person," the source adds.

Michelle Trachtenberg at the 15 Years of Siriano Party at Nic's On Beverly on Nov. 2, 2023.

Gilbert Flores/WWD via Getty

After news of Trachtenberg's death broke, sources told PEOPLE that the actress had recently undergone a liver transplant and may have had complications. 

A separate source told PEOPLE that Trachtenberg had been "really really down emotionally" and had "told friends she was struggling" in the last year.

"She was really, really sick and open with those in her circle about how much she was struggling," the source said. "She was "pale, gaunt, very thin, and dealing with health issues."

Trachtenberg's friend says she was sick "off and on," but notes she did not divulge more details about her health — just "that she had been sick."

Blake Lively (left) and Michelle Trachtenberg in 'Gossip Girl'.

The CW/Giovanni Rufino /Landov

The actress never publicly shared any health conditions, but she shut down critics in January 2024 who made comments about her appearance after she shared a selfie on Instagram. "Fun fact. This is my face," she wrote. "Not malnutrition no problems. Why do you have to hate? Get a calendar."

In another post, the actress said, "I've received several comments recently about my appearance. I have never had plastic surgery I am happy and healthy. Check yourself haters."

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Trachtenberg was best known for her roles on Gossip Girl and Buffy the Vampire Slayer. She made her breakthrough as the titular character in Harriet the Spy in 1996, alongside industry greats Rosie O'Donnell and J. Smith-Cameron. She also starred in EuroTrip, 17 Again and Ice Princess.

Following her death, several stars paid tribute to her life, including her Harriet the Spy costars Rosie O'Donnell and J. Smith-Cameron, as well as her Gossip Girl costars Blake Lively Chace Crawford,  Taylor Momsen and Ed Westwick. Her Buffy the Vampire Slayer costars Sarah Michelle Gellar, James Marsters and David Boreanaz also shared tributes in her honor.

"She was electricity. You knew when she entered a room because the vibration changed. Everything she did, she did 200%," Lively wrote in her tribute. "She laughed the fullest at someone's joke, she faced authority head on when she felt something was wrong, she cared deeply about her work, she was proud to be a part of this community and industry as painful as it could be sometimes, she was fiercely loyal to her friends and brave for those she loved, she was big and bold and distinctly herself."

And, notes Lively, "The world lost a deeply sensitive and good person in Michelle."