Her father and mother, Charles and Sarah Harbour, were milliners, furriers, and dressmakers and had both been born in Russian Poland.
[2] By 1919, Harbour was working for Raphael Tuck & Sons, a publisher which produced postcards, calendars, and books.
[4] Her prints were very successful, and Raphael Tuck made an arrangement with Reinthal & Newman of New York to hand-print the works for the United States market.
She also illustrated My Book of Mother Goose Nursery Rhymes and Hans Christian Andersen's stories.
[7] In 1927, she illustrated The Yellow Fairy Book of the Newbery classics series, which was edited by Andrew Lang and published by David McKay Company.