This may be more related to your other question. Ethel appears on census data with parents Alford/Alfred M Davis and Mary. Later with Ernest and her sister Gladys. Most Census data indicates Alford was b. in MO in 1872 and Mary E was b. in IL. One census of Ethel and Ernest indicated he was b. in KS.
You might try searching the many siblings of Ethel using the free search tool at: https://familysearch.org/search to see if you can find more on Alford and Mary?
Examples below:
U S Census, 1900 Canadian Township, Cleveland, Ok
Citing this Record: "United States Census, 1900," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MMGC-M8X
Head Alfred Davis M 28 Feb 1872 MO/TN/IL married abt 1892
Wife Mary Davis F 26 ? Jan or Jun 1874 IL/IL/IL 4 children 3 living
Dau Effee Davis F 8 AR
Dau Ethel Davis F 5 AR
Son Frank Davis M 1 OK
U S Census, 1910 Wetumka Ward 1, Hughes, OK
Citing this Record: "United States Census, 1910," index and images, FamilySearch (https://familysearch.org/pal:/MM9.1.1/MLQM-9JC
Head Alford M Davis M 38 1872 IL
Wife Mary E Davis F 35 1875 IL/IL/IL
Dau Ethel Davis F 14 Oklahoma
Son Arthur Davis M 11 Oklahoma
Dau Gladys Davis F 9 Oklahoma
Son Stephen Davis M 5 Oklahoma
Dau Ruby Davis F 3 Oklahoma
Dau Selma Davis F 0 Oklahoma
Nephew William Snoder M 17 Oklahoma
U S Census, 1920 Calvin, Hughes, Ok
Head Alford Davis M 47 1873 MO/TN/AR
Wife Mary Davis F 35 1885 IL/IL/IL
Son Arther Davis M 21 Oklahoma
Son Stephen Davis M 14 Oklahoma
Dau Ruby Davis F 12 Oklahoma
Dau Selma Davis F 9 Oklahoma
Son Fred Davis M 7 Oklahoma
