NEW YORK CITY, NY — Michelle Trachtenberg, known for her roles in “Buffy the Vampire Slayer” and “Gossip Girl”, has passed away.

She was 39 years old.

According to The New York Post who was first to report her passing, Trachtenberg recently underwent a liver transplant.

The NYPD confirmed she was found unresponsive by her mother around 8 a.m. Wednesday at One Columbus Place, a 51-store luxury apartment complex on Central Park South and pronounced dead by EMS workers, sources said.

Trachtenberg was born on October 11, 1985. She made her television debut in commercials when she was three years old and she played a recurring role as Lily Montgomery on the soap opera All My Children. Her first major role was for a Nickelodeon series, “The Adventures of Pete and Pete,” as the young Nona F. Mecklenberg. She gained further fame as a child actress playing the lead role of Harriet in “Harriet the Spy”, and in her teen years, became a household name as Buffy’s younger sister, Dawn Summers, in the critically acclaimed, “Buffy the Vampire Slayer”. From 2007-2012, she played Georgina Sparks in “Gossip Girl.”

The cause of death is being investigated, however it is not being deemed as suspicious. Fans had been concerned about her recent appearance of looking thin, gaunt, and frail in her Instagram posts.