Michelle Trachtenberg, known for roles on Gossip Girl and Buffy The Vampire Slayer, has died.

She was 39 years old.

Trachtenberg’s mother found her dead on Wednesday morning at the actresses' New York City apartment.

According to sources, Trachtenberg had recently undergone a liver transplant and was experiencing complications.

Trachtenberg started her career as a child actor on the Nickelodeon show The Adventure of Pete & Pete. She also starred in the film Harriet the Spy.

She portrayed Dawn, the younger sister of Buffy The Vampire Slayer, on the television series that ran in the early 2000s.

Trachtenberg also starred as Georgina Sparks on Gossip Girl from 2008 through 2012.