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

Comedian and former Nickelodeon child star Kenan Thompson shared a video on Instagram of the two of them on Nick, writing: ...

Kenan Thompson shared a sweet tribute to fellow Nickelodeon alum Michelle Trachtenberg, whose sudden death was announced on ...

PEOPLE confirmed the late actress' sudden death at age 39 Michelle Trachtenberg's sudden death is being felt across Hollywood ...

Kenan Thompson shared a touching tribute to his fellow Nickelodeon alum Michelle Trachtenberg, who died at age 39 on ...

Kenan Thompson paid tribute to his 'friend' and fellow Nickelodeon child star Michelle Trachtenberg after her death at age 39 on ...

Blake Lively, Sarah Michelle Gellar, David Boreanaz, Ed Westwick, Kim Cattrall, Kenan Thompson, Melissa Joan Hart and more ...

Kenan Thompson shared a sweet tribute to fellow Nickelodeon alum Michelle Trachtenberg, whose sudden death was announced on Feb. 26.

Following the heartbreaking news that the “Buffy the Vampire Slayer” star died Wednesday at the age of 39, friends and former colleagues took to social media to honor the late actress.

Related: Michelle Trachtenberg Shares Cryptic Throwback Photos in Final Posts Ahead of Her Death at 39 Kenan Thompson called Trachtenberg "Our first Nick movie star" in his Instagram tribute ...

Before Kenan Thompson and Judd Apatow were household names — and Ben Stiller was still on the rise — they teamed up for ...