Sarah Michelle Gellar is paying tribute to Michelle Trachtenberg on what would have been her 40th birthday.
Eight months after Trachtenberg died from diabetes complications at age 39, the Buffy the Vampire Slayer star is looking back on her decades-long friendship with her onscreen little sister.
“When you turned 16, it was hard not to still see you as the little girl I met on All My Children,” Gellar began her Saturday Instagram tribute. “When you turned 21, I had to teach myself to not see you as the little sister anymore. I can’t imagine what 40 would have been like. This I know… it would be filled with love. Happy birthday.”
The heartfelt birthday message was accompanied by a clip from Buffy in which the two actresses share a meaningful embrace, and set to the tune of Charlie Puth and Wiz Khalifa’s song, “See You Again.”
Richard Cartwright/20th Century Fox/Courtesy Everett Collection
Trachtenberg, who starred as Buffy’s younger sister Dawn Summers on the beloved teen drama, was found dead in her New York City apartment on Feb. 26. In April, The New York City Office of Chief Medical Examiner released a statement announcing her cause of death as complications from diabetes mellitus. The manner was determined to be natural.
In addition to Buffy, Trachtenberg was known for her work on Gossip Girl and as the child star of Harriet the Spy. She also starred in such notable projects as Inspector Gadget, The Adventures of Pete & Pete, 17 Again, Mysterious Skin, EuroTrip, and the Disney figure-skating comedy Ice Princess.
The loss prompted an outpouring of love from fans and former costars alike, including several of Trachtenberg’s pals from Buffy. In her initial February response to Trachtenberg’s death, Gellar referenced their onscreen sisterhood by echoing a speech that Buffy gives to Dawn in the show’s season 5 finale. “Michelle, listen to me,” she wrote on Instagram. “Listen. I love you. I will always love you. The hardest thing in this world, is to live in it. I will be brave. I will live… for you.”
Allyson Hannigan, who shared the screen with Trachtenberg as her friend and confidante Willow Rosenberg, wrote on Instagram that she was “deeply saddened by the news of Michelle’s passing.” She continued, “She brought a loving energy to the set of Buffy. My thoughts are with Michelle’s family and friends.”
Nicholas Brendon, whose character Xander Harris played a major role in Dawn’s life, shared a video stating that while he didn’t see her much” of Trachtenberg after wrapping on Buffy, she was “like a beam of light” whenever they worked together.
Richard Cartwright/UPN/Courtesy Everett
Another major Buffy player, James Marsters, wrote on Instagram. “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.”
Kristine Sutherland, who played Buffy and Dawn’s mom Joyce, mourned the young actress in a statement, writing, “I am devastated by the news of Michelle’s death. The day she joined the Buffy family she brought a joy and innocence with her along with her talent. She was lovely to work with and will be missed. My heart goes out to her family.”
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Though Trachtenberg took on fewer roles in the last years of her life, following her death, an associate revealed that she had been working to produce a “sharp, biting” screenplay based on Jerry Oppenheimer’s book Toy Monster: The Big, Bad World of Mattel.
“The only scripts I remember staying with me like that in recent memory were two. Here Comes the Flood by Simon Kinberg and Toy Monster around 2019. Because they were the two best, by a landslide,” Casey Tebo told PEOPLE, adding that he is “doing everything I can to get this movie made, we just need to find the right director, and I promise we will get it made for her.”