Isabelle Emilie de Tessier was born in Paris in 1850. She became an actress, using the pseudonym Marie Duval, and collaborated with C. H. Ross, whom she married about 1869, on the early Ally Sloper strips in Judy. Originally brought in to ease Ross's workload by inking his pencils, she took over the art completely by 1870, considerably improving the graphic quality of the strip. Her strips were reprinted in Ally Sloper: A Moral Lesson (1873), Ally Sloper's Comic Crackers (1875-1887), and Ally Sloper's Summer Number (1880-88). Ross sold all rights to the character in the early 1880s, and when the regular paper Ally Sloper's Half Holiday was launched in 1884 it was drawn by other artists, although it did include reprints of Ross and de Tessier's strips with signatures removed.
She also edited C. H. Ross's Variety Paper, De and produced numerous spot illustrations, cartoons and full page comic strips for Judy and Fun, and was the author of Queens and Kings and Other Things (1880), a collection of illustrated nonsense verse published under the pseudonym of Princess Hesse Schwartzbourg. She died in Wandsworth in 1890.
- Denis Gifford, ‘Ally Sloper group (act. 1867–1923)’, Oxford Dictionary of National Biography, Oxford University Press, 2004, accessed 7 July 2012
- Ally Sloper on Don Markham's Toonopedia
- Charles H.Ross & Marie Duval, 'Ally Sloper' - 1867, Andy's Early Comics Archive
- Marie Duval on Lambiek Comiclopedia
- Alan Clarke, Dictionary of British Comic Artists, Writers and Editors, The British Library, 1998, p. 53