Sáez was born in Montevideo, which at the time was part of the Spanish Viceroyalty of the Río de la Plata. She was the daughter of Francisco Sáez, a wealthy businessman, and Josefa Pérez.[1] On 17 August 1819, she married Luis Vernet, whom she had met when he set up a commercial enterprise with Conrad Rücker. They had seven children.[1]
While living in Puerto Luis on the Falkland Islands Sáez kept a personal diary, which was preserved amongst the archive of her husband's papers donated to the Argentine National Archive.[2] She was accomplished at playing the piano; travelers and personalities who passed through the colony, referred to the "refinement" and cultural level of the Vernets. On several evenings she played the piano and sang.[3] Robert Greenhow wrote that Sáez "played Rossini's music with great gusto."[4]
The diary was referenced by the Argentine revisionist author Antonio Montarcé Lastra as part of his argument for Argentina's claim for sovereignty of the Falkland Islands.[1][6] Sáez was also used as the basis of the principal character in two historical romance novels.[7][8] Ernesto Cilley Hernández, Sáez's great-grandson, published the diary in bilingual Spanish-English form in 1989.[9]
In 2012, the National Library of the Argentine Republic held a research scholarship contest named for Sáez in relation to Argentina's claim over the Falkland Islands.[10] As part of International Women's Day 2015, the Museo Malvinas e Islas del Atlántico Sur of Buenos Aires presented the exhibition Malvinas, mi casa, which included a series of watercolors reflecting life in the Falklands in 1829, based on Sáez's diary and lectures by her descendants on Argentina's claim to the Falklands.[11]
^"DISCURSO MARCELO LUIS VERNET". Retrieved 5 August 2018. "En las páginas del diario de María, las cartas, papeles oficiales y contratas de trabajo, que hoy conservamos en el Archivo General de La Nación, aún late la vida de todos los días del Puerto de la Soledad de Malvinas."
^Gregorio Quesada, Vicente (1881). La cuestion de límites con Chile [The Question of Borders with Chile] (in Spanish). Impr. y librería de Mayo, de C. Casavalle. p. 56. Retrieved 2 August 2018 – via Google Books.
^Marcaletti, Romina Mariana (2013). "The "Malvinas question" and its symbols: experience, memory and subjectivity". Malvinas in the University: 2012 Essay Contest(PDF). Buenos Aires: Ministry of Education. pp. 64–88.
^"Día de la Mujer en el Museo Malvinas" [Women's Day at the Falklands Museum] (in Spanish). Falklands and South Atlantic Islands Museum. Archived from the original on 8 March 2015. Retrieved 2 August 2018.