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In the 1880 census it is stated that Harden McKenney was the niece of Samuel Pace and that William Pace was his nephew: 1880 Federal Census for Jefferson, Cole County, Missouri 261/261 Samuel B. Pace / - / 34 yo b. MO / parents b. VA [b. 1846] William B. Pace / nephew / 28 yo b. VA / parents b. VA / farmer HardenaMcKenney / niece / 29 yo b. VA / parents b. VA / keeping house Jessie L. McKenney / dau [of Hardena?] / 8 yo b. MO / parents b. VA
In earlier census records both Hardena Pace and William Pace were enumerated in the household of John W. Pace & his wife, Henrietta. I believe, but do not have proof that John Wilson Pace was another son of Benjamin F. Pace.