Buffy the Vampire Slayer stars mourn death of 'little sister' Michelle Trachtenberg

Michelle Trachtenberg's Buffy the Vampire Slayer co-stars have shared tributes mourning the death of their 'little sister'.

Trachtenberg was tragically found dead at the age of 39 by emergency services at One Columbus Place, New York, at around 8am on Wednesday (February 26), the NYPD has confirmed.

Police said her death is not being treated as suspicious and an autopsy will determine her cause of death.

In a statement, Trachtenberg's representatives said: “It is with great sadness to confirm that Michelle Trachtenberg has passed away. The family requests privacy for their loss.”

Tributes have since been flooding in for the TV star, who joined the fifth season of the supernatural drama as Dawn Summers, Buffy's younger sister.

Emma Caulfield, who starred as Anya Jenkins, said the cast had 'lost a little sister' in a post on Instagram.

Caulfield wrote: “I’m so sorry your bright light died so young. Our Buffy family lost a little sister today.

“Rest in peace lovely Mish Mish. You were loved.”

Actress Alyson Hannigan, who played Willow Rosenberg in the show, also shared some nostalgic snaps of Trachtenberg including pics from when they shared scenes together.

Hannigan said: “I am deeply saddened by the news of Michelle’s passing.

“She brought a loving energy to the set of Buffy. My thoughts are with Michelle’s family and friends.”

Meanwhile, James Marsters, who played the British vampire Spike, shared a selfie of the pair and described his co-star as a 'beautiful soul'.

“My heart is heavy today,” he wrote. “We have lost a beautiful soul.

“Michelle was fiercely intelligent, howlingly funny, and a very talented person. She died much too young and leaves behind scores of people who knew and loved her.

“My heart goes out to her family who are good people and are suffering the greatest loss anyone could bear.

“I hope everyone can give them space to heal in this most difficult time. Godspeed Michelle. You are missed.”

Other famous celebs who worked with Trachtenberg have also penned heartbreaking tributes, including her Gossip Girl co-star, Blake Lively, who described her old friend as 'kind' and 'electric' who 'laughed the fullest'.

Ed Westwick, who played Chuck Bass on the hit American teen drama, added he was 'sending prayers' after learning of her death.

Sex and the City star, Kim Cattrall, who shared a photo of the two from the film Ice Princess, wrote: “Rest in peace sweet Michelle.”

US comedian, Rosie O’Donnell, who starred in the 1996 movie Harriet the Spy with Trachtenberg, said her death was 'heartbreaking'.

“I loved her very much,” O'Donnell said in a statement to People. “She struggled the last few years. I wish I could have helped.”

The tragic news comes as Buffy actress Sarah Michelle Gellar, 47, teased on social media that she is 'on the path' to reviving the show with a team of 'four unbelievably talented women'.

Trachtenberg rose to fame from the young age of three, appearing in Nickelodeon television series Adventures of Pete and Pete which aired from 1994 to 1996, followed by the 2004 movie, Eurotrip.

She hit global success for her roles as Georgina Sparks in Gossip Girl and as Dawn Summers in Buffy the Vampire Slayer, the latter of which saw her nominated for three Saturn Awards and bag a Young Artist Award.

Trachtenberg also voiced the character of Judy Reilly in American adult animated comedy series Human Kind Of which premiered on Facebook Watch and starred in movies such as 2005's Ice Princess and appeared in 17 Again (2009) alongside Zac Efron.

LADbible Group has contacted NYPD and Michelle Trachtenberg's representatives for comment.

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