Buffy The Vampire Slayer and Gossip Girl actress Michelle Trachtenberg has died aged 39.

Trachtenberg was discovered deceased on Wednesday in her New York City apartment near Columbus Circle around 8 a.m. local time by her mother, according to police sources as reported by ABC News.

It was further reported the actress recently underwent a liver transplant and ‘may have been experiencing complications.’ 

She is believed to have died of natural causes and police are not treating the death as suspicious, sources added to the New York Post.

Trachtenberg was best known for her work as Buffy’s (Sarah Michelle Gellar) younger sister Dawn Summers in 66 episodes of Buffy the Vampire Slayer from 2000-2003. 

She also had a recurring role as ‘The Witch of the Upper East Side’ Georgina Sparks in Gossip Girl alongside Blake Lively spanning 2008-2012.

Buffy The Vampire Slayer and Gossip Girl actress Michelle Trachtenberg has died aged 39 – pictured 2023 

Trachtenberg was best known for her work as Buffy’s ( Sarah Michelle Gellar ) younger sister Dawn Summers in Buffy the Vampire Slayer spanning 2000-2003

Trachtenberg had previously sparked fears for her health last year 

In recent years Trachtenberg had sparked concern for her health after sharing troubling social media posts in which she looked frail. 

In 2023 Michelle reprised her role in two episodes of the second (and final) season of HBO Max’s Gossip Girl reboot.

Trachtenberg’s last major gig was executive producing and hosting the 13-episode true-crime docuseries Meet, Marry, Murder for Tubi TV in 2021.

In 2018, she had voiceover gigs on her buddy Seth Green’s animated spoof Robot Chicken on Adult Swim as well as the Facebook Watch animated series Human Kind Of.

Trachtenberg raised concerns among her fans after sharing 10 Instagram posts over the past three weeks ahead of her death.

Prior to her shock passing, the star was extremely active on social media.

Her final Instagram post, uploaded seven days ago, was a throwback picture of her attending the Killing Kennedy premiere at the Saban Theatre on November 4, 2013 in Beverly Hills.

‘I wanted to look like naughty #tinkerbelI wanted to look like naughty #tinkerbell,’ she captioned the picture, which showed her posing on the red carpet.

The Brooklyn native also had a recurring role as ‘The Witch of the Upper East Side’ Georgina Sparks in 28 episodes of The CW teen soap Gossip Girl spanning 2008-2012

Trachtenberg was found dead Wednesday in her New York City apartment near Columbus Circle (pictured) just after 8am local time by her mother, police sources told ABC News

Trachtenberg is pictured in Hollywood in 2020 

Trachtenberg was just 14 when she was cast on Buffy (pictured 2001 with Sarah Michelle Gellar) 

In 2023 Michelle reprised her role as the wedding-spoiling, manipulative socialite in two episodes of the second (and final) season of HBO Max’s Gossip Girl reboot

Trachtenberg’s last major gig was executive producing and hosting the 13-episode true-crime docuseries Meet, Marry, Murder for Tubi TV in 2021

Trachtenberg shared this Instagram snap on February 12 captioned ‘eye of the tiger’

Trachtenberg is pictured in 1996 film Harriet The Spy with Rosie O’Donnell

Michelle uploaded two more selfies she took and, again, fans clarified they’re not worried about plastic surgery or malnutrition but rather her ‘thinning hair and yellow eyes.’

Days prior, she shared another older picture and joke about not letting the ‘Sunday scaries’ get to her.

She was clearly in a nostalgic mood as she also recently shared a snap, taken in 2011 at the School of American Ballet Winter Ball, and a cheeky suggestion for those without Valentine’s Day plans to watch her true crime docuseries, Meet, Marry, Murder.

Additionally, she shared a sweet tribute to her boyfriend, talent agent Jay Cohen, who she described as ‘the man who sits still long enough for’ her to ‘paint his face.’

The post included a sweet snap of them from Halloween dressed as Dr. Jekyll and his alter ego, Mr. Edward Hyde.

On February 8 and February 12, Trachtenberg shared more recent selfies in the same location, which appeared to be taken on an outdoor patio.

Last year the star hit back at ‘haters’ who expressed concern over her health and appearance.

The former child star – who boasts 1.1M Instagram/Twitter followers – wrote‘Fun fact. This is my face. Not malnutrition no problems. Why do you have [to] hate? Get a calendar.’

The drama began when Michelle shared a snap of herself about to get her hair done at Tracey Cunningham’s Mèche salon in Beverly Hills.

A fan asked: ‘Michelle [you] look sick. [Are you] ok?’

Trachtenberg replied: ‘@cathy_critz explain to me how I look sick. Did you lose a calendar and not realize I’m not 14? I’m 38. How sad for you to leave such a comment.’

The next day, she posted yet another selfie with the defiant caption: ‘I’ve received several comments recently about my appearance. I have never had plastic surgery. I am happy and healthy. Check yourself haters.’

‘Nobody is talking about plastic surgery. They are talking about your liver shutting down,’ one follower wrote.

Another typed: ‘I really don’t think anyone was implying you had plastic surgery. We are generally concerned about you. Your eyes are yellow, your hair is [thinning] majorly, you look sick.’

‘People are just worried that your eyes are yellow and all your hair is falling out,’ another penned.

‘I think they are worried for your health.’ 

One follower wrote: ‘Anyone with yellow eye balls is not well and needs to see a doctor.’

Trachtenberg began her acting career aged three on  Nickelodeon television series The Adventures of Pete & Pete (1994–1996). 

In 1997 aged 11 she won a Young Artist Awards for her performance as Maggie in CBS’ Meego. 

The star also appeared in 2004 hit EuroTrip.

Her breakout role came as Georgina Sparks on  Gossip Girl before landing the part of Dawn Summers on Buffy.

The latter won her another Young Artist Award and three Saturn Award nominations.

Trachtenberg was nominated for a Daytime Emmy Award for her role as host of the Discovery Kids series Truth or Scare (2001–2003).

Her other screen credits include  Mysterious Skin (2004) and Black Christmas (2006).

She also starred on the NBC television series Mercy (2009–2010) as Chloe Payne.