Helen Moore Sewell, born in Vallejo, California, was an American artist and children’s author especially known for her illustrations for American author Laura Ingalls Wilder’s Little House series and for books of classic literature.
Sewell began painting and drawing at an early age. At the age of 12, she became the youngest person ever to attend the Pratt Institute. In 1924 she illustrated her first book, Susanne K. Langer’s The Cruise of the Little Dipper, and Other Fairy Tales. She illustrated her own book, ABC for Everyday, in 1930 and a year later collaborated with her sister on Building a House in Sweden. In 1932 she illustrated Little House in the Big Woods, Laura Ingalls Wilder’s first book. Others followed in the Little House series. She also illustrated classic works by American poet Emily Dickinson and British authors Jane Austen, Charlotte Brontë, and A.A. Milne. During her career Sewell illustrated more than 50 books.
(source: https://www.britannica.com/biography/Helen-Moore-Sewell)