Ní Chéileachair, Síle (1924–85), teacher and Irish language author, was born 24 July 1924 in Cúil Aodh, Co. Cork, one of six children of farmer Dónall Bán Ó Céileachair and his wife, Siobhán Ní Mhulláin. Although born in the Gaeltacht, she grew up in a bilingual environment. She came from a literary and musical family. Her father was a renowned seanchaí from whom the Irish literary scholar Gerard Murphy (qv) collected folklore material in 1932. Murphy also encouraged him to write his life story, published in 1940 under the title Scéal mo bheatha. Her brother Donncha Ó Céileachair (qv) was a prolific writer in Irish and her maternal uncle was the songwriter and musician Dónall Ó Mulláin (qv). She spent a period in Coláiste Bhríde teacher training college in Falcarragh, Co. Donegal, and afterwards in Mary Immaculate College, Limerick. She was employed as a national schoolteacher in Harold's Cross, Dublin, before her marriage in 1953. From the end of the 1950s until her death she was employed as a teacher in Crumlin.
Around 1946, together with her brother Donncha, she attended a literature course in Cúil Aodh presented by Daniel Corkery (qv) (1878–1964). This course concentrated on the modern short story and was influential in her choosing the short story as a genre in her later work. It is noteworthy that the siblings dedicated their joint short story collection Bullaí Mhártain (1955) to Corkery, stating that it was he who ‘taught’ them. The work has as its central theme the changes taking place in Irish society and culture and contains nine stories by her. There is a degree of uncertainty as to whether she wrote all the stories attributed to her, however. For example, Pádraigín Riggs suggests that Corkery was actually the author of ‘Blimey! Peaidí Gaelach eile’. It is significant that Ní Chéileachair's name was omitted from the entry for Bullaí Mhártain in The Arts in Ireland: a chronology (1982), 226. Stylistically, the two authors were very different. According to Ó Dúshláine, Donncha's stories are more realistic while Síle's are measured and written according to rules. The result is that Ní Céileachair provides a typical textbook example of the modern short story. He also notes the influence of Edgar Allan Poe on her work and suggests that often her aim was to startle the reader. Her short story ‘An phiast’ won an award at the 1949 oireachtas competition and was published for the first time the following year.
Throughout the 1950s, along with her brother Donncha, she was active in Cumann na Scríbhneoirí, an organisation founded to encourage and promote the writing of Irish-language literature, and regularly attended its meetings. Only a small number of women were members and according to Máirín Ní Mhuiríosa (qv) amongst that group only Ní Chéileachair, Máiréad Ní Ghráda (qv) and Eibhlín Ní Chathailriabhaigh (1910–2001) took an active part in the meetings. She married Donal Ó Cochláin in 1953 and they had three sons and three daughters.
Ní Chéileachair died 26 August 1985 and was buried at Bohernabreena cemetery, Co. Dublin.