Author. She received notoriety for the thirty-one children's books written during the 20th century in both the English and Irish languages. She wrote a collection of stories including “The Emerald Ring and Other Irish Fairy Stories” in 1951, “The Stolen Child and Other Stories” in 1961, “The Four-leafed Shamrock” in 1964 and the “Miser's Gold” in 1970. Devoted to the Irish language or Gaelic, she also authored plays including “Cluichidhe na Gaedhilge” in 1935. Born Jane or Janice O'Flanagan, she was the ninth of eleven children of Laurence and Margaret Flanagan. She was a trained teacher who taught at Francis Xavier's, a national school in Dublin, Ireland. She joined the Maud Gonne's organization “Daughters of Ireland” under the English version of her name “Jennie Flanagan” instead of “SinéadNi Fhlannagain,” the Irish version that she used later in life. Wit a passion for the Irish culture being preserved, in her spare time she taught Gaelic to the Gaelic League offices on Parnell Square in Dublin. One of her students was Eamon de Valera, a mathematics teacher who would become her husband. They married on January 8, 1910 and were the parents to five sons and two daughters. At the age of twenty years old, their son Brian was killed when thrown from a horse while riding in the park in July of 1935. She grieved this loss the rest of her life and never could visit his grave site. Her husband's adventures such as fighting for Ireland especially the failed Easter uprising; his sentence to death that was commuted to life imprisonment, and then merciful amnesty; or his long stay in the United States greatly impacted her and her children's lives. With five children under the age of six years old, she was penniless and depended on help from others outside their family to survive. Years later, she would tell how the nuns had helped her, and she taught Gaelic to them and the pupils at their school. From 1916 to 1923, her husband was not at home providing for his family but involved in a life of bloodshed and rebellion. Depending on the source, her political beliefs vary. In 1920 to see her husband, it was arranged that she was smuggled to the United States using a false passport. Even with all this hardship, she managed to be an outstanding mother with the children each distinguishing themselves in professional careers such as a lawyer, college professors or a physician. Later, she was the wife of the third President of Ireland for 14 years rarely appeared in public but continued her work with children. Her books have become collector's items with the asking price for an original hardcover of “The Emerald Ring and Other Irish Fairy Stories” being $350. Not only did she author books, she translated books to Gaelic. Both her and her husband died within months of each other at an age over 90 years old; she died nearly eight months after her husband and one day before what would have been their sixty-fifth wedding anniversary. In 2016 a commemorative plaque to honor her was unveiled by the Balbriggan Historical Society in County Dublin, Ireland.