Michelle Trachtenberg, an actress known for her roles in projects like Buffy the Vampire Slayer, Eurotrip, Disney’s Ice Princess, and more, passed away on Wednesday at the age of 39.

According to reports on Trachtenberg’s passing, the actress was found by her mother Wednesday in her New York City apartment. The actress did recently undergo a liver transplant, according to ABC News, but no official cause of death has been disclosed as of yet.

Trachtenberg’s acting career began in the mid-1990s, with the child star appearing on projects like Law & Order, All My Children, and more. In 1994, Trachtenberg appeared on the Nickelodeon series The Adventures of Pete & Pete and went on to become a mainstay on Nickelodeon broadcasting. In 1996, she starred in the Nickelodeon coming-of-age comedy film Harriet the Spy.

After her stint with Nickelodeon, Trachtenberg broke out in a starring role on the hit supernatural drama Buffy the Vampire Slayer, where she played Dawn Summers, the little sister to Sarah Michelle Gellar’s Buffy Summers, for 66 episodes. Around the same time, she also starred in the 2004 teen comedy Eurotrip, as well as the 2005 Disney teen sports dramedy Ice Princess.

In 2008, Trachtenberg began appearing on the hit drama Gossip Girl, where she played Georgina Sparks in a recurring role throughout the series. She continued to work throughout Hollywood in recent years, even hosting a documentary series titled Meet, Marry, Murder.

ComingSoon extends its condolences to the family and friends of Trachtenberg.