Ida Rentoul Outhwaite was the second surviving child of Reverend John Laurence Rentoul and Annie Isobel Rentoul (née Rattray) (q.v.), and her sister was Annie R. Rentoul (q.v.). She benefited from the encouragement of her artistic and literary family, and while she was being formally educated at Presbyterian Ladies' College, found time to contribute to magazines which her family produced in their home at Ormond College, University of Melbourne.
In 1903 six fairy stories, illustrated by Ida and written by her sister, were published in New Idea, and the following year the sisters produced Mollie's Bunyip, which used an Australian setting as a background for the adventures of fairies and elves which appeared as in European tradition. Ida also illustrated a book with text by her mother, Mollie's Staircase (1906), and in 1907 the Rentoul sisters attended the Australian Exhibition of Women's Work where they showcased their Australian Songs for Young and Old, with music by Georgette Peterson (wife of Franklin Peterson.)
On 9 December 1909 Ida married Arthur Grenbry Outhwaite (q.v.), manager of the Perpetual Executors and Trustees Association of Australia Ltd. Ida and Grenbry had six children in the decade following their marriage, and Ida published little during that time. However, her first work with coloured illustrations, Elves and Fairies, was published in 1916, with the assistance of her business-savvy husband. Grenbry also wrote the text for some books illustrated by Ida.
Now well-known, Ida exhibited her work almost annually from 1916 to 1928, including in Paris and London during her visit to Europe in 1920. Her last two exhibitions were held in 1933, and during the 1930s her popularity steadily declined as her works became seen as old-fashioned.
After Grenbry Outhwaite died in 1938 (both their sons had died in action in World War II), Ida lived with her sister in Caulfield, and eventually died there, survived by her two daughters.
Source: Australian Dictionary of Biography Online, http://www.adb.online.anu.edu.au. Accessed 17 May 2007.