Mackenzie Christine Foy (born November 10, 2000) is an American actress. She is best known as Renesmee Cullen in the 2012 film The Twilight Saga: Breaking Dawn – Part 2, which earned her a Young Artist Award nomination as Best Supporting Young Actress in a Feature Film; as the young Murphy in the 2014 space epic Interstellar, for which she received a Saturn Award for Best Performance by a Younger Actor among other awards nominations; and as Clara in Disney's The Nutcracker and the Four Realms.