There's a KY death record for Millard which list's his parents as Tom KERR and Martha TAYLOR.
Millard and Pearl KERR appear in Monroe Co, KY in the 1920, 1930 and 1940 censuses. In one Millard is listed as born in KY and in the others he was born in TN. Their children were: Fred, Wheeler, Lily, Jack, Della, Gladys, Dessie, Prentice, Osby, Venie, Albert, Nina and Inell.
Millard registered for the WWI draft in Cumberland Co, KY. On his draft registration card he states that he was born in Celina, TN.
I'm having trouble finding the family in the 1910 census, but there's a likely match for Millard in 1900 in Cumberland Co, KY: KERR, Martha J. b. May 1847 in TN, married 34 yrs, 8 children born, 6 children living, both parents b. TN, Son John b. Aug 1879 in TN, Daugther Bell b. May 1885 in TN, Son Millard b. July 1888 in TN.
I found this tree that indicates Millard was married to a Fannie LOGAN either before or after Pearl: https://familysearch.org/ark:/61903/2:2:9324-D75
According to that Millard's parents were William Thomas KERR and Mary Jane TAYLOR.
The 1880 census for Clay Co, TN has this family: KERR, William T. age 37 b. KY, both parents b. KY, Wife Martha J. age 33 b. TN, father b. NC, mother b. TN, Son Alexander R. age 13, Daughter Lucy F. age 7, Son John A. age 1, Daughter Mary S. age 5, and son Charles H. age 10.
This would match with Martha's age in 1900 and the son John who is age 21 in the 1900 census.
The 1910 census for Martinsburg, Monroe Co, KY has this family: SHORT, Albert W. age 44 b. KY, Wife Martha A. age 41 b. KY and children: Pearlie J, 17, Fannie L, 16, Oliva, 14, Anna T, 13, Bertha F., 11, Chiston C, 6, Cora, 4, Rosa M, 2, and a boarder, CLOYD, Martha A. age 61.
In 1900 they are in the same location, but the father's name is different: SHORT, Jake A. b. Feb 1865 in KY, married 8 yrs, both parents b. KY, Wife Martha b. Jan 1868 in KY, 5 children born, 5 children living, both parents b. KY, Dau Pearl b. Jan 1893, Dau Fannie b. Feb 1895, Dau Oliva b. Mar 1896, Dau Annie T. b. Mar 1897, son Bedford b. Mar 1898.