Ernestine Moller Gilbreth, Mrs. Carey (April 5, 1908 – November 4, 2006) was an American author.
Born in New York City, she was the daughter of Lillian Moller Gilbreth and Frank Bunker Gilbreth, early 20th-century pioneers of time and motion study and what would now be called organizational behavior.
The upbringing of the twelve Gilbreth children was chronicled in the successful, comic memoir Cheaper by the Dozen (1948, adapted in a 1950 film). The book, as well as a sequel, Belles on Their Toes (1952), was written by Carey with one of her younger brothers, Frank B. Gilbreth Jr.