Michelle Trachtenberg and Sarah Michelle Gellar pictured together in 2007

Sarah Michelle Gellar has likened the loss of Michelle Trachtenberg to the loss of a sister.

On Thursday, Sarah Michelle paid tribute to her Buffy The Vampire Slayer co-star with a poignant line from their hit TV series, in which the two played unconventional siblings.

Michelle — who was best known for her roles in Buffy, Gossip Girl, Harriet The Spy and Ice Princess — was found dead in her New York City apartment on Wednesday, at the age of 39.

Sarah Michelle wrote on Instagram, alongside a slideshow of photos of herself and Michelle over the years: ”Michelle, listen to me. Listen. I love you. I will always love you. The hardest thing in this world, is to live in it. I will be brave. I will live… for you.”

The quote is a reference to a pivotal scene in the season five finale of Buffy.

In the scene, Michelle’s character, Dawn, learns that her blood........

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