Blake Lively Reminisces About Gossip Girl Co-Star Michelle Trachtenberg’s ‘Delicious Caramel Lip Gloss’ and Other Charming Memories

 Lively also reflected on the "challenging" nature of the film industry in her heartfelt tribute to her former co-star.

Blake Lively is urging people to cherish their loved ones following the unexpected passing of her Gossip Girl co-star Michelle Trachtenberg at age 39 on Feb. 26.

Lively, 37, paid tribute to Trachtenberg in an emotional Instagram Stories post on Wednesday, shortly after the NYPD confirmed her death in New York City to PEOPLE. The two actresses appeared together in the 2007-2012 hit series, with Trachtenberg portraying the scheming Georgina Sparks, a frenemy to Lively’s Serena van der Woodsen.

Sharing a throwback photo from their Gossip Girl days, Lively reflected on the first time she met Trachtenberg. "She was electricity. You knew when she entered a room because the vibration changed. Everything she did, she did 200%," Lively wrote.

"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, and she was fiercely loyal to her friends," Lively continued. "She was big and bold and distinctly herself."

Lively also reminisced about a small yet thoughtful detail—Trachtenberg’s signature caramel-scented lip gloss. "She didn't just want to shine on camera; she wanted to create a pleasant experience for those around her, even in the smallest ways," she wrote.

Reflecting on lost time, Lively expressed regret over missed opportunities to reconnect. "Time passes. You take for granted that you’ll get the chance to see an old friend," she shared. "The real tragedies in life are the ones that blindside you on an idle Tuesday."

Lively concluded with heartfelt words: "The world lost a deeply sensitive and good person in Michelle. May her work and her huge heart be remembered by those lucky enough to have known her."

Other Gossip Girl cast members, including Chace Crawford and Ed Westwick, also paid tribute. Crawford, who played Nate Archibald, recalled, "Michelle was one of a kind. She was a force of nature—so unapologetically funny and magnetic. Just a terrible loss. Love you ❤️"

Trachtenberg was found "unconscious and unresponsive" on Wednesday morning. While the cause of death has not been confirmed, sources revealed she had recently undergone a liver transplant and had been struggling with health issues.

Known for her sharp wit and mischievous on-screen presence, Trachtenberg reprised her role as Georgina Sparks in the 2023 Gossip Girl reboot, marking her final television appearance.