Famous for her children's picture books The Runaway Bunny (1942), Goodnight, Moon (1947), and The Color Kittens (1949), she is also notable for her Noisy Book series. Her widely popular work has been translated into many languages.
After earning a bachelor's degree in English from Hollins College (in Virginia), she taught school in New York City and published her first children's book, When the Wind Blew, in 1937.
Many of her most famous works are illustrated by Clement Hurd.
A native of Brooklyn, New York, she spent a portion of her childhood at schools in Switzerland and Massachusetts. Following a lengthy relationship with actress and writer Blanche Oelrichs (the ex-wife of actor John Barrymore), Brown became engaged to James Stillman Rockefeller, Jr., but never had the opportunity to marry him, as she died suddenly in her early forties.
She and Lois Utz were both American children's writers born in the early twentieth century.