Blake Lively is mourning her "fiercely loyal" and "brave" Gossip Girl costar Michelle Trachtenberg after her death at age 39.

Michelle Trachtenberg's co-stars and fellow celebrities are speaking out after the "Gossip Girl" and "Harriet the Spy" star ...

Blake Lively broke her social media silence on Wednesday to pay tribute to her late “Gossip Girl” co-star Michelle ...

Blake Lively, Rosie O'Donnell and other Hollywood figures are paying tribute to Michelle Trachtenberg, who died at 39.

Blake Lively took to her Instagram Stories Wednesday evening to share a lengthy tribute to her "Gossip Girl" costar Michelle ...

Gossip Girl star Blake Lively has shared a poignant tribute to her late co-star Michelle Trachtenberg, who passed away ...

Lively shared a photo of the day she met Trachtenberg, writing, "The world lost a deeply sensitive and good person" ...

Michelle Trachtenberg's death Wednesday left her former co-stars like Blake Lively, Rosie O'Donnell, Melissa Gilbert and ...

Actress Blake Lively has urged the world to remember Gossip Girl co-star Michelle Trachtenberg’s “work and huge heart” ...

Blake Lively has taken to Instagram to issue an emotional tribute to her Gossip Girl co-star Michelle Trachtenberg after she ...

Michelle Trachtenberg was not interested in wading into the legal waters surrounding her Gossip Girl costar Blake Lively in ...

The “Buffy the Vampire Slayer” star was found dead in her New York City apartment on Wednesday after going into cardiac arrest.