Edith Alice Unnerstad (née Tötterman) (28 July 1900 – 29 December 1982) was a Swedish author, particularly known for her children's books.
Unnerstad was born in Helsinki, Finland, the daughter of Swedes Axel and Ingeborg Tötterman. In 1908, when she was eight years old, her grandmother, a pilot's widow in Åland, died. The Tötterman family left Helsinki and moved to the grandmother's house on Åland which her mother had inherited. In 1910, the family moved to Sweden and settled in Södertälje, and in 1912 they moved to . After the First World War the family moved back to Aland.
Writing later, she referred to an observation by the British children's writer A. A. Milne that children's writers are created early: "Perhaps Mr. Milne was right. Very likely the pattern for my future profession was already minutely drawn when I was seven or eight." Unnerstad's own literary career began when her sister was hospitalized with scarlet fever and requested something to read. Afraid that her family's much loved books would not return safely from the hospital as they would have to pass through disinfection ovens, the 11-year-old Unnerstad decided to write her sister a new book instead. She wrote new chapters daily, and delivered each to the hospital on her way to school. According to Unnerstad "The 'book', if I remember right, turned out to a horrifying mixture evidently inspired by my idols at the time: Cooper, Jules Verne, Captain Marryat and Swedish Finland's great old story-teller, Topelius.....After that there was no turning back." Three years later, she had two poems and a story published in a magazine, and spent the proceeds on a pair of patent-leather pumps, a bag of toffee and a copy of Atala by Chateaubriand. Unnerstad attended Detthowska School and art school in Stockholm. In 1924, Unnerstad married a civil engineer Arvid B. Unnerstad. They had a daughter, Lena.