Trachtenberg's co-stars in "Gossip Girl" shared similar sentiments. Blake Lively, who played Serena van der Woodsen in the series, wrote in an Instagram story that Trachtenberg "w

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.

Michelle Trachtenberg’s former “Buffy the Vampire Slayer” costar Sarah Michelle Gellar is looking back at their time together on screen and off, one day after Trachtenberg died in New York City.