It took me a few days to hunt down my source for Thomas' middle name. My sources on ancestry.com do not show his middle name, only a middle initial "M". My source for Thomas McGruber Yandle is:

The Early Yandells of North Carolina, and Some of Their Descendants, 1737-1982; by Velma Nancyann Yarbrough; Gateway Press, Inc, Baltimore, MD, 1982; page 410: Part V, viii, son of Sherrod/Sheard Yandels / Yandles lists Thomas' family; page 417: Part V, Sources of Information, see #31 Tom Yandle, 1900 US Census, Union County, NC; & #32 Thomas McGruber Yandle. See below for information regarding Source #32.

Source #32 reads:
Thomas McGruber Yandle
LDS Family Sheet submitted by C. A. Yandle of Columbia, SC. [Ms. Yarbrough stated: "He [[C. A. Yandle]] stated his source of information was his Bible."]

Now to speculation on my part:
The C. A. Yandle maybe Thomas' grandson and child of Oscar Lee Yandle, named Chalmers Alonzo Yandle, born 1925, who lived in Columbia, Richland County, SC. SGY

Research by Suzzette Yandle
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Spouses:
1) Martha "Mattie" Long, born Mar 1860 in NC: source: book The Early Yandells of North Carolina, 1982.; and married 13 Dec 1882 in Union County, NC, married by Esquire J. S. Baucom. Source of marriage: North Carolina Marriage Index, 1741-2004 on ancestry.com.

2) Daisy Ford / Foard, married 22 May 1918 Union County, NC. Source: North Carolina, Marriage Records, 1741 - 2011, ancestry.com.
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Children with Mattie, per Early Yandells of North Carolina:
Fred Yandle
Lilly Yandle
Oscar Lee Yandle
Virgie Yandle [note: her name is Roberta aka Bertie]
Cornelius Yandle
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Full names of children with dates per Suzzette's research on ancestry.com:
Fred Yandle , born 1883
Lillie Elizabeth Yandle, born 1884, died 1964
George McDonald Yandle, born 1887, died 1972
Oscar Lee Yandle, born 1888, died 1939
Roberta aka Bertie Yandle, born 1890-1892, died 1969.
Cornelius Woodrow Yandle, born 1893, died 1959.
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