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

Michelle Trachtenberg, a former child star who appeared in the 1996 “Harriet the Spy” hit movie and went on to co-star in two buzzy millennial-era TV shows — “Buffy the Vampire Slayer” and “Gossip Girl” — has died.

The veteran actress, born in New York and raised in Brooklyn before moving to L.A., moved seamlessly from the big and small screens throughout her decades long career.