Agnès Rosenstiehl was born in Paris, France in 1941 into a family of artists. She studied French literature at the Sorbonne and Composition at the Conservatoire National and went on from there to become one of France's most esteemed children's book authors. Among her many works are "Mon Larousse" a dictionary for youngest readers, "Le Livre de la Langue Francaise" (The Book of the French Language) published by Gallimard and "Paris-Pékin par le Transsibérien" (Paris-Pekin by the Transiberian), which she illustrated and co-wrote with her husband, a mathematician, after an inspirational family trip. Agnès happens to be an expert on the poem's of France's illustrious poet, Arthur Rimbaud, and her work has been published in several professional journals.
Agnès is most well-known for her young heroine Mimi Cracra, who has appeared in over 100 books and pamphlets and has inspired a French television series. Rosenstiehl's books have been translated into eight languages, including Japanese and Chinese. Agnès conceived Mimi Cracra’s English language début, Silly Lilly and the Four Seasons, and the eagerly-awaited follow-up, Silly Lilly in What Will I Be Today? especially for the TOON Books collection.
Between Agnes and her husband, mathematician Pierre Rosenstiehl, they have seven children and fifteen grandchildren. They live in a country house with a garden, hidden in the center of Paris.