Sarah Chauncey Woolsey was an American children's author who wrote under the pen name Susan Coolidge. Woolsey was born January 29, 1835, into the wealthy, influential New England Dwight family in Cleveland, Ohio. Her father was John Mumford Woolsey (1796–1870) and mother was Jane Andrews. She spent much of her childhood in New Haven Connecticut after her family moved there in 1852. Woolsey worked as a nurse during the American Civil War (1861–1865), after which she started to write. The niece of the author and poet Gamel Woolsey, she never married, and resided at her family home in Newport, Rhode Island, until her death. She edited The Autobiography and Correspondence of Mrs. Delaney (1879) and The Diary and Letters of Frances Burney (1880). She is best known, however, for her classic children's novel, What Katy Did (1872). The fictional Carr family was modeled after the author's own, with Katy Carr inspired by Susan (Sarah) herself, and the brothers and sisters modeled on Coolidge's four younger Woolsey siblings.