Harrington is perhaps best known for her role as the main character's sister in the 1993 film What's Eating Gilbert Grape. Her character was aged around 20 though the Actress herself was 35 at the time. She has also had a prominent role in the 1986 film Maximum Overdrive, written and directed by horror Novelist Stephen King, in which she played the love interest to Emilio Estevez's character.