Trachtenberg, who co-starred with Gellar on the hit TV series, was found dead in her apartment on Tuesday. She was 39.

Gellar's tribute to her late costar echoes a monologue she delivered in the supernatural drama's season 5 finale.

Gellar is honoring her late 'Buffy the Vampire Slayer' costar, who died on Wednesday, February 26, with a powerful quote from ...

Michelle Trachtenberg’s former “Buffy the Vampire Slayer” costar Sarah Michelle Gellar is looking back at their time together ...

Sarah Michelle Gellar has paid tribute to her former Buffy The Vampire Slayer co-star Michelle Trachtenberg following her ...

Sarah Michelle Gellar is paying tribute to her late "Buffy the Vampire Slayer" co-star Michelle Trachtenberg after her tragic ...

Cast members of "Buffy the Vampire Slayer," "Gossip Girl" and more are remembering their co-star Michelle Trachtenberg​ after ...

Sarah Michelle Gellar mourned the death of “Buffy the Vampire Slayer" co-star Michelle Trachtenberg in an Instagram post.

Sarah Michelle Gellar paid tribute to the late Michelle Trachtenberg after the actress died at age 39.

Blake Lively, Sarah Michelle Gellar and other Hollywood figures are paying tribute to Michelle Trachtenberg, who died at 39.

Michelle Trachtenberg’s sudden death left an empty hole in the hearts of fans and former costars whom she worked with ...

Fans and friends alike are mourning the loss of Michelle Trachtenberg, who died this week at age 39. Sarah Michelle Gellar ...