Born Inez Dean on 20 March 1894, Jeffus' parents were physician James N. Dean, who was from Alabama, and Emma Caldonia Calloway-Dean, who was a Texan native. She was born when her father and mother were thirty-two and eighteen years old respectively. Her father died in 1957, aged 96, having been born in 1861. Her mother died in 1975 less than two years before her 100th birthday, having been born in 1876.
Jeffus also had a total of four siblings: Lena, born 1892, Essie, born 1895, Kent, born 1899, and finally Jimmie, born prior to 1 April 1906. Lena had unfortunately died by 1910.
Jeffus' first husband was fellow Texan native James M. Parker, seven years her senior. She was no longer married to him by later than 1930 according to findings by Gerontology Research Group correspondent Filipe Prista Lucas, as Jeffus' second husband, Hayne Jeffus, was then still married to his first wife according to the fifteenth population census of the United States, conducted beginning from 1 April 1930. Hayne Jeffus lived from 26 July 1893 to 8 March 1967, dying at the age of 73.
Jeffus, who had taken residence in California for a time during the 1920s before returning to Texas, had at least three children: May Dean (later May Dean Burnap), James, and Ellis Clifford Parker. Ellis Clifford was the only child who had predeceased Jeffus by the time of her death, having died on 2 February 2006, eight and a half months before Jeffus herself. He was 85 at the time of his death, Jeffus having given birth to him in May 1920.
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| The gravesite of Hayne and Inez Jeffus |
She passed away in Nacogdoches, Texas, as that state's second-oldest living resident on 16 October 2006, aged 112 years, 210 days, a week behind Arbella Ewing (13 March 1894 - 22 March 2008, aged 114 years, 9 days).
Prior to her validation, it had been believed that the second-oldest living Texan then was Martha Wiley (28 August 1894 - 16 October 2006, aged 112 years 49 days). Coincidentially, Wiley and Jeffus both died on the same day. Assuming Jeffus predeceased Wiley, Wiley would have indeed been that state's second-oldest person at the time of her own death, albeit for less than twenty-four hours. Even if Wiley had predeceased Jeffus, it would have counted for one of the closest longevity-related title misses in history, of less than 24 hours.
At the time of her death, she was the 14th-oldest living person and to this day still remains one of the 250 oldest undisputed people on record, tied with Margaret Russell (31 October 1892 - 29 May 2005) and a living woman who is currently the 20th-oldest living person, Susannah Jones of New York, United States, born 6 July 1899 and also aged 112 years 210 days as of 1 February 2012.
Her age was not validated while she was alive, as her online obituary was later discovered by Filipe Prista Lucas, who was able to validate her age via census records using family names provided in the obituary. She was afterwards added to the GRG database on 6 November 2006.
V.V., who owns another supercentenarian-related blog, Supercentenarian Research, helped with the writing of this article.