PEOPLE confirmed the late actress' sudden death at age 39 Michelle Trachtenberg's sudden death is being felt across Hollywood. Several celebrities paid tribute to the Gossip Girl alum after the NYPD confirmed her death at age 39 to PEOPLE on Feb.

News of Michelle Trachtenberg's death prompted tributes from her friends and former "Buffy," "Harriet the Spy," and "Gossip Girl" costars.

O’Donnell was Trachtenberg’s A-list co-star in Harriet the Spy, the 1996 kids movie that marked Trachtenberg’s first major film role (she was just 10 when filming began). O’Donnell played “Ole Golly,” a nanny and mentor to Harriet, the precocious snoop and writer played by Trachtenberg.