Note: Census records vary on the birth year. The birth date shown on the 1900 Census is used here. In the various census records she is listed as Ann, Elizabeth and Ann E.

She is likely buried in an unmarked grave next to her husband Elder Henry R. McCoy.
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1850 Chambers County, (Dist. 19) AL Census:

#H814

Thomas Willoughby 60M Farmer R$___ (10-Slaves; 1-Runaway)Born GA
Aggy Willoughby 60F Born GA
John Willoughby 25M Farmer Born GA
ANN WILLOUGHBY 21F Born GA
Elias Willoughby 21M Farmer Born GA
Jane Willoughby 20F Born GA
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1860 Chambers County, (Milltown) AL Census:

#H832

Thomas Willoughby 70M Farmer R$3,500 P$17,500 (13-Slaves) Born GA
Agnes Willoughby 70F Born NC
Robert Willoughby 40M P$1,200 Born GA
John Willoughby 34M Overseer P$4,500 (1-Slave) Born GA
ANNE WILLOUGHBY 32F Born GA
Anne Hayes 65F Born GA
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1870 Chambers County, (Milltown) AL Census:

#H84

Robert Wiloby 40M Farming Born GA
ELIZABETH WILOBY 38F Keeping House Born GA
Lemuel Turner 22M (Black) Farm Hand Born AL
Charity Turner 25M (Black) Farm Hand Born AL
Jane Turner 3F (Black) Born AL

Note: Robert's age did not change between the 1860 and 1870 Census. Ann Elizabeth's changed by six years instead of ten.
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Chambers County, AL Marriage Record Book 7 Page 203b:

Henry McCoy and ELIZABETH WILLOUGHBY on May 4, 1875, by J.W.H. Cliett, MG. T.B. Carlisle, 2nd Bondsman.
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1880 Chambers County, (Milltown) AL Census:

#H9

Henry McCoy 52M Farmer Born GA
ELIZABETH McCOY 50F Keeping house Born GA
John McCoy 22M Works Farm Born AL
Hull McCoy 12M Works Farm Born AL
Dan McCoy 10M Works Farm Born AL
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1900 Chambers County, (Trammell X-Roads) AL Census:

#H74

Wm. Willoughby 80M Farmer Born Jan. 1820 in GA (Widower)
ANN McCOY 70F Sister Born May 1830 in GA (Widow. Mother of 0 children.)
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1910 Chambers County, (Milltown) AL Census:

#H30

Cornelius Cox 64M Farmer Born GA
Nancy E. COX 62F Wife Born AL
Mamie B. Cox 20F Daughter Farm Laborer Born AL
ANN E. McCOY 84F Aunt Born GA (Widow)
Robert Shidell(?) 21M (Black) Hired Man/Farm Laborer Born AL
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