Michelle Trachtenberg‘s actual cause of death revealed

Michelle Trachtenberg's real cause of death is laid bare.

After a lot of speculation and examinations, The New York City Office of Chief Medical Examiner has confirmed the Gossip Girl alum died after complications of diabetes mellitus.

The 39-year-old was found dead in her apartment in New York City.

Earlier, a source told PEOPLE that Trachtenberg had been "really really down emotionally" and had "told friends she was struggling" in the last year.

"She was really, really sick and open with those in her circle about how much she was struggling," the insider said. "She was “pale, gaunt, very thin, and dealing with health issues."

Upon her death, co-star Blake Lively also shared a photo with Michelle, recounting time from the show.

“She was electricity. You knew when she entered a room because the vibration changed. Everything she did, she did 200%,” Lively admitted.