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

Trachtenberg passed away at age 39. The New York native broke through with, among other early roles, her starring turn in the film Harriet the Spy

Michelle Trachtenberg, the actress who rose to fame as a child star with films like “Harriet the Spy” and went on to have memorable roles on TV shows including “Gossip Girl,” has died, according to an NYPD source.