Actress Michelle Trachtenberg, known for the television series "Buffy the Vampire Slayer" and "Harriet the Spy," has died at the age of 39.
Police sources confirmed her death to both ABC News and the New York Post. The cause of death is not yet known and is reportedly not being investigated as suspicious. She had recently undergone a liver transplant.
ABC reports that the actress's mother found her dead in a New York apartment.
Trachtenberg was a child actress who began her career at age three in commercials before appearing on the Nickelodeon show "The Adventures of Pete & Pete" and the soap opera "All My Children."
She later landed her first leading role in the comedy adventure "Harriet the Spy" alongside Rosie O'Donnell. She followed her film career with a role in "Inspector Gadget" alongside Matthew Broderick.
In the series "Buffy the Vampire Slayer" in 2000 she played the role of Dawn Summers until the show ended three years later.
Subsequent film roles included the teen comedy "EuroTrip," Gregg Araki's acclaimed drama "Mysterious Skin," and a leading role in the Disney drama "Ice Princess." She also had a role in the hit HBO series "Six Feet Under."
The following years saw roles in shows such as "House" and films such as "Black Christmas" in 2006 before she landed the role of Georgina Sparks in the teen drama series "Gossip Girl."
Trachtenberg's last big-screen role was the 2014 sci-fi thriller "The Scribbler," but she has a project that's not yet in the works, a drama about mental illness called Spyral.