Gossip Girl cast Blake Lively, Chace Crawford & Kelly...

CELEBRITY tributes have poured in for Gossip Girl and Buffy the Vampire Slayer star Michelle Trachtenberg after he tragic death. A number of famous faces have shared their heartbreak over the loss of the talented actress, who was sadly passed away aged 39 - and now several of Michelle's Gossip Girl co-stars have paid tribute.

Image Credit: The Sun [Michelle Trachtenberg at the Victoria's Secret Fashion Show.]

Michelle's body was found in her New York City apartment on Wednesday, just days after she posted selfies that left fans concerned for her health. The actress was found at around 8 am at a building in Manhattan, New York City, located near Central Park, by her mother, police sources told ABC News.

Image Credit: The Sun [Photo of Michelle Trachtenberg at the 2005 Sundance Film Festival.]

Some of Michelle's Gossip Girl co-stars have paid tribute to the late actress since the news of her passing broke. Blake Lively shared a snap of herself with Michelle from the their Gossip Girl days, and described the late star as having an "electric" personality.

Image Credit: The Sun [Serena and Georgina from Gossip Girl.]

She then penned: "Everything she did, she did 200%. She laughed the fullest at someone's joke, she faced authority head on when she felt something was wrong, she cared deeply about her work, she was proud to be a part of this community and industry as painful as it could be sometimes, she was fiercely loyal to her friends and brave for those she loved, she was big and bold and distinctly herself.

Image Credit: The Sun [Michelle Trachtenberg and Blake Lively at the CFDA Fashion Awards.]

"Time passes. You take for granted that you get the chance to see an old friend. To paraphrase, the real tragedies in life are the ones that blindside you on an idle Tuesday. Hold those you love and have loved dear.". She added: "The world lost a deeply sensitive and good person in Michelle. May her work and her huge heart be remembered by those who were lucky enough to experience her fire.".

Image Credit: The Sun [Chace Crawford and Michelle Trachtenberg.]

Chace Crawford is another Gossip Girl co-star who has paid tribute to Michelle, with him writing: "Michelle was one of a kind. "I remember her coming on set for the first time and just absolutely owning it. She was a force of nature and just so so unapologetically funny and magnetic...remembering those years with a big smile.

Image Credit: The Sun [Michelle Trachtenberg and Chace Crawford paying tribute.]

"Just a terrible loss. Love you.". Meanwhile, Kelly Rutherford shared a snap of Michelle and simply added some white heart emojis and a dove emoji,. Ed Westwick also took to social media to remember Michelle. He shared a snap of her and penned: "So sad to hear of the passing of @michelletrachtenberg sending prayers.".

Image Credit: The Sun [Gossip Girl cast members Penn Badgley, Michelle Trachtenberg, Leighton Meester, Chace Crawford, and Ed Westwick.]

And Taylor Momsen is another Gossip Girl star who has paid tribute. "In shock," she began her moving post about Michelle in the wake of her passing. She went on: "When I met this girl 17 years ago I knew we’d be friends… she was smart and sassy, bold and sensitive, funny as f*** and filled with fire.

Image Credit: The Sun [Gossip Girl cast members Ed Westwick, Leighton Meester, Michelle Trachtenberg, and costume designer Eric Daman at a publication celebration.]

"She was simply awesome… I will miss you every day my love… I think we truly understood each other and I am so grateful to have had a friend like you in my life for so long.". She added: "I hope you’re f***ing up heaven for both of us… My heart is on the floor. I’m still in shock but I needed to honor her, she deserves more than this.".

Image Credit: The Sun [Michelle Trachtenberg and Taylor Momsen at a Reebok event.]

Leading the tributes when the news broke saw Sex and the City star Kim Cattrall also share a touching message. Kim wrote: "This is Heartbreaking. So talented, much too young," she commented under Variety's post. She added: "RIP Sweet Beauty.". Kim then shared a photo of them starring together in 2005 movie the Ice Princess and captioned it: "Rest in peace sweet Michelle.".

Image Credit: The Sun [Kim Cattrall and Michelle Trachtenberg in a scene from a movie.]

Matilda and Mrs Doubtfire star Mara Wilson shared a sweet tribute to the late actress. She wrote: "My heart is breaking for my childhood friend." along with a photo of Michelle. "Your memory will be a blessing, Michelle.". Sabrina The Teenage Witch actress Melissa Joan Hart paid tribute to Melissa.

Image Credit: The Sun [Kim Cattrall and Michelle Trachtenberg in a scene.]

The pair starred together in 90s sitcom Clarissa Explains It All. "I'm heartbroken to hear of the passing of Michelle Trachtenberg!! So young, so talented and so sweet!" she wrote. "Here is a fun scene from when she was on #ClarissaExplainsItAll.". She continued, "I think this was about 1992 and the episode was an idea I had about babysitting a total nightmare.

Image Credit: The Sun [Michelle Trachtenberg in a black jacket with pink highlights in her hair.]

"But Michelle was nothing like her character and even this young, we got along wonderfully.". Michelle's former Buffy co-star James Marsters called her a "beautiful soul" and said it was the "greatest loss". He wrote: "My heart is heavy today. 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.". He continued: "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.". Michelle Trachtenberg began her career as a child actress, starring in over 62 movies and TV shows before her sudden death at age 39. Notable roles throughout her career include:. The star also made cameo appearances in major TV shows:.