Michelle Christine Trachtenberg (October 11, 1985 – February 26, 2025) was an American actress who achieved widespread recognition as both a child star and a prominent television and film performer. Beginning her career at the age of three in television commercials, she landed her first major credited television role in Nickelodeon's The Adventures of Pete & Pete (1994–1996) and transitioned to the big screen with the title role in the 1996 family comedy Harriet the Spy.

Trachtenberg rose to international prominence as a teenager and young adult through iconic television and film projects. She is best known for portraying Dawn Summers in the fantasy drama series Buffy the Vampire Slayer (2000–2003) and playing the memorable villain Georgina Sparks on the CW teen drama series Gossip Girl (2008–2012). Her diverse film credits also include the comedies EuroTrip (2004) and 17 Again (2009), as well as the Disney ice skating film Ice Princess (2005).

On February 26, 2025, Trachtenberg was found dead at the age of 39 in her New York City apartment. The New York City Office of Chief Medical Examiner later announced that she died from natural causes resulting from complications of diabetes mellitus.