Michelle Trachtenberg, best known for her role in "Gossip Girl", died due to natural causes and may have suffered complications following a liver transplant, according to police sources who spoke with ABC News. The actress, 39, was found unresponsive by her mother in her New York City apartment near Columbus Circle on Wednesday, just after 8 a.m. local time.
Authorities informed the Daily Mail that no foul play is suspected in her passing. Meanwhile, sources told TMZ that Trachtenberg had been struggling with alcohol-related issues. The medical examiner's office will conduct an autopsy to determine the exact cause of death. However, authorities have still launched an investigation into her death.
Untimely Death

"On Wednesday, February 26, 2025, at approximately 0801 hours, police responded to a 911 call of an aided individual at 1 Columbus Place, within the confines of the Midtown North Precinct," police said in a statement.
"Upon arrival, officers observed a 39-year-old female unconscious and unresponsive. EMS responded to the location and pronounced the victim deceased.
"Criminality is not suspected. The Medical Examiner will determine the cause of death. The investigation remains ongoing."
The actress had a liver transplant recently, the NY Post reported. "The Buffy the Vampire Slayer" star began her career at an early age, landing her first role on Law & Order in 1991.
In recent months, Trachtenberg shared a series of troubling photos on Instagram, where the acclaimed actress has 800,000 followers. In the photos, she appeared noticeably thin and fragile, leading some fans to remark on her drastic weight loss or speculate about drug use.
In January, Trachtenberg addressed the concerns, assuring followers that she was "happy and healthy" and had never undergone plastic surgery. However, she didn't say if she was suffering from drug abuse.
Born in New York City on October 11, 1985, Trachtenberg landed her first credited role at just nine years old on the beloved 1990s Nickelodeon series "The Adventures of Pete and Pete," where she played the eccentric Nona F. Mecklenberg.
She later starred in several children's films and TV shows, making her big-screen debut in 1996 as the lead character in "Harriet the Spy."
Return to Showbiz after a Break

As she grew older, Trachtenberg transitioned to more mature roles, including a three-year run as Dawn Summers, the younger sister of the titular heroine in "Buffy the Vampire Slayer." She also portrayed the cunning and scheming antagonist Georgina Sparks on "Gossip Girl," a series that spanned six seasons.
In 2021, Trachtenberg made bombshell allegations against "Buffy the Vampire Slayer" creator and "Avengers" director Joss Whedon, who was 55 at the time.
She claimed he had been physically abused her during the filming of the show and alleged that a "rule" was enforced on set to prevent him from being alone with her in a room. She shared these claims in a cryptic Instagram post.
Whedon later refuted the allegations in an interview with New York Magazine.
On her last birthday, October 11, Trachtenberg shared a glamorous photo on Instagram with the caption, "39 and I'm feeling fiiiiiine," which received over 32,000 likes.