Michelle Trachtenberg was found “unconscious and unresponsive” in her New York apartment, pronounced dead at scene according to police statement.

The 39 year old was a former child star who appeared in the 1996 “Harriet the Spy” hit movie and went on to co-star in two buzzy millennial-era TV shows, “Buffy the Vampire Slayer” and “Gossip Girl”.

According to report, no foul play was suspected and the New York Medical Examiner is investigating the cause of death.

Gary Mantoosh, the deceased representative on Wednesday shared that: “The family requests privacy for their loss.”

Trachtenberg was 8-year-old when she began playing Nona Mecklenberg on Nickelodeon’s “The Adventures of Pete & Pete” from 1994 to 1996 and then starred in the title role in the film adaptations of “Harriet the Spy” and “Inspector Gadget,” opposite Matthew Broderick.

She joined the cast of “Buffy” in 2000, playing Dawn Summers, the younger sister of the title character played by Sarah Michelle Gellar between 2000 and 2003.

In 2001, Trachtenberg received a Daytime Emmy nomination for hosting Discovery’s “Truth or Scare.”

She played a math prodigy and aspiring figure skater in “Ice Princess,” in 2005

In the 2004, she appeared in teen sex comedy “EuroTrip,” she co-starred with Zac Efron and Leslie Mann in 2009’s “17 Again” and played a murderous stalker and abductor on an episode of “Criminal Minds.”

For “Killing Kennedy,” the 2013 film in which she played the wife of Lee Harvey Oswald, around 80% of Trachtenberg’s dialogue was in Russian. She had learned the language from her mother growing up.

She also starred on the NBC medical series “Mercy” (2009–2010) opposite Taylor Schilling.

Of recent, she hosted the true-crime docuseries “Meet, Marry, Murder” on Tubi.

She was nominated as a TV villain at the Teen Choice Award in 2012.

Hollywood mourned her loss as some took to social media to grieve her demise

David Boreanaz on Instagram stated: “so very sad.. horrible news.”

 Melissa Gilbert: “My heart aches for your family and all those who loved you so.”

Rosie O’Donnell, who starred alongside Trachtenberg in her “Harriet the Spy” debut, said her death was “heartbreaking:” “I loved her very much. She struggled the last few years. I wish I could have helped.”

Glee star Chris Colfer wrote: “Michelle was the absolute sweetest and one of the most supportive people I knew.”