Michelle Trachtenberg, Star of Harriet the Spy and Buffy the Vampire Slayer, Dies at 39

Actress Michelle Trachtenberg has died aged 39.

Michelle Trachtenberg, the actress who rose to fame as a child star in Harriet the Spy and later became known for her roles in Buffy the Vampire Slayer and Gossip Girl, has died at the age of 39, according to an NYPD source.

Police responded to a 911 call on Wednesday just after 8 a.m. local time and found a woman unconscious and unresponsive inside a Manhattan apartment. She was later identified as Trachtenberg, according to an NYPD spokesperson. Paramedics arrived at the scene and pronounced her deceased.

Actress Michelle Trachtenberg pictured in 2009. (AP)

"Criminality is not suspected," the NYPD said in a statement, adding that the investigation remains ongoing. The Medical Examiner’s office will determine her official cause of death.

Earlier on Wednesday, an NYPD source stated that Trachtenberg had a recent medical issue and that her death appeared to be related to natural causes.

Trachtenberg in Buffy the Vampire Slayer. (Stan / 20th Television / Disney)

Trachtenberg began her acting career at the age of three, appearing in commercials before securing a role on "The Adventures of Pete & Pete." She gained widespread recognition as the lead in Nickelodeon's 1996 film "Harriet the Spy." Her subsequent performances as Dawn Summers on "Buffy the Vampire Slayer" and Georgina Sparks on "Gossip Girl" solidified her status in the entertainment industry.

Following the news of her passing, several of Trachtenberg's former co-stars and colleagues have expressed their condolences. Rosie O'Donnell, who co-starred with her in "Harriet the Spy," shared her sorrow on social media, stating, "Just heard the heartbreaking news about Michelle. She was a bright light and a true talent." Ed Westwick, her "Gossip Girl" co-star, posted, "Devastated to hear about Michelle. She brought joy to so many with her performances."

Michelle Trachtenberg and Sarah Michelle Gellar on the set of Buffy The Vampire Slayer. (20th Century Fox Television)

The cause of Trachtenberg's death has not been officially disclosed. The Medical Examiner's office will determine the exact cause as the investigation continues. Fans and colleagues alike mourn the loss of an actress who made a significant impact on both television and film.

She recently appeared in the Gossip Girl reboot. (Foxtel/Binge)