The ‘Gossip Girl’ actress was found dead in New York City on the morning of Wednesday, Feb. 26

Amanda de Cadenet and Michelle Trachtenberg. Photo: Frazer Harrison/Getty; Gilbert Flores/WWD via Getty

Amanda de Cadenet is remembering her friend Michelle Trachtenberg after her death.

Following the Wednesday, Feb. 26 news of Trachtenberg’s death at age 39, the 52-year-old media personality and photographer mourned the loss of the actress.

“Sweetheart Michelle. . What sad news this morning to wake up to. It feels weird and awful to be posting this, but I want to acknowledge your death because I cared about you,” her tribute began. The Instagram post included a photo of a younger Trachtenberg posing for the camera. 

“I will always remember you as the young vivacious woman I met when I took this photo of you …,” de Cadenet continued. “Seeing your face from the hospital bed when we FaceTimed recently, even though you did not look like you, your sweetness and humor were still alive.”

“I will not share the details of our conversations over the last 6 months, but you knew that death was a high possibility,” de Cadenet wrote.

“I am only sorry that the outcome was not a better one. Wishing you a peaceful transition sweet friend and may your spirit finally rest. ,” de Cadenet concluded.

She did not elaborate further on her friendship with the actress or on Trachtenberg’s hospitalization.

Michelle Trachtenberg on February 09, 2020 in West Hollywood, California. Jemal Countess/Getty

The Gossip Girl actress was found “unconscious and unresponsive” by police on the morning of Wednesday, Feb. 26. A cause of death has not been confirmed. However, Trachtenberg had recently undergone a liver transplant, sources tell PEOPLE.

Following the news of her death, ABC News reported her liver transplant may have led to “complications.”

A source told PEOPLE that in the year prior, Trachtenberg was “really down emotionally.” She also had been dealing with “health issues.”

“She told friends she was struggling,” the insider said. “She was really, really sick and open with those in her circle about how much she was struggling.”

Trachtenberg never publicly shared any health conditions. But in January 2024, she did respond to commenters on her Instagram when they suggested she was unwell after she shared a selfie to her grid. “Fun fact. This is my face,” she captioned the post. “Not malnutrition no problems. Why do you have to hate? Get a calendar.”

Michelle Trachtenberg on January 04, 2020 in Los Angeles, California. Randy Shropshire/Getty

Trachtenberg is best known for her roles on Buffy the Vampire Slayer and Gossip Girl. She got her start in commercials before landing her roles on Nickelodeon’s The Adventures of Pete & Pete and Harriet the Spy.

She also had several other prominent roles across film and TV over the years, including in EuroTrip, 17 Again and Ice Princess. Her last credited role was in 2023, reprising Georgina on Max’s Gossip Girl reboot.

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Her former costars from her various projects also mourned her, including Harriet the Spy costars Rosie O’Donnell and J. Smith-Cameron, Buffy the Vampire Slayer costars Alyson Hannigan and James Marsters, Gossip Girl costars Blake Lively, Ed Westwick, and Chace Crawford, and many more.