Trachtenberg starred as the cunning Georgina Sparks on the beloved CW series, appearing in each of the six seasons and reprising her role in the recent reboot.

Blake Lively took to her Instagram Stories Wednesday evening to share a lengthy tribute to her “Gossip Girl” costar Michelle Trachtenberg. “This is the first day I met Michelle,” Lively wrote, sharing a photo of her and Trachtenberg on “Gossip Girl.

Blake Lively broke her social media silence on Wednesday to pay tribute to her late “Gossip Girl” co-star Michelle Trachtenberg, who died Wednesday morning at 39. In an Instagram Story, Lively remembered Trachtenberg as a “fiercly loyal” and “kind person, through and through.”