Michelle Christine Trachtenberg (October 11, 1985 – February 26, 2025) was an American actress. After beginning her career in commercials at age three, she made her television debut in her first credited role on the Nickelodeon series The Adventures of Pete & Pete (1994–1996) and her feature film debut in the 1996 comedy Harriet the Spy. As a child actress, Trachtenberg starred in several Nickelodeon productions. In 1997, she won a Young Artist Award for her performance in CBS' sitcom Meego. She also played Penny Brown in Disney's 1999 superhero comedy film Inspector Gadget. Trachtenberg found success on the supernatural drama series Buffy the Vampire Slayer (2000–2003) as Dawn Summers, the younger sister of Buffy, for which she won another Young Artist Award and earned her three Saturn Award nominations. She was also nominated for a Daytime Emmy Award for her role as the host of the Discovery Kids series Truth or Scare (2001–2003). In her late teens and early 20s, Trachtenberg rose to further prominence in the film EuroTrip (2004) and as Georgina Sparks on the CW series Gossip Girl (2008–2012). During the mid-2000s, she also had a starring role in the film Ice Princess (2005) and supporting roles in the films Mysterious Skin (2004) and Black Christmas (2006). She also starred in the film 17 Again (2009) and on the NBC series Mercy (2009–2010). In the 2010s, Trachtenberg was in several television films, including Killing Kennedy (2013) and Sister Cities (2015), and in the science fiction film The Scribbler (2014). She provided the lead voice of Judy in Facebook Watch's adult animated web series Human Kind Of (2018) and executive produced the teen drama web series Guidance (2015–2017) and Tubi's true crime series Meet, Marry, Murder (2021).