Did a little sleuthing and found what looks like the pre-California venue of James William, Ralph F, and William Edward IZARD.They show up in the 1900, 1910 and 1920 Cook county IL census in the household of William IZARD.Based on this and state of issue of their SSN's, suspect they migratedto CA no earlier than 1930's.
Tried Cunningham's in OK but too numerous without other clues to come to any conclusions.Ona's SSN issued in CA, so she probably was in CA when issued; 1930's on.Migration could have been because of Dust Bowl and/or work on West Coast because of WW 2.
CADI combos give some interesting possibilities for Ona.Usng mother maiden JONES and father CUNNINGHAM and OK birth place, I got 3 other females born around same time frame, one dying in Tulare county.Using CUNNINGHAM as surname, OK birth place, and TULARE death place, I get 3 males born around same time frame plus a female with mother maiden IZARD.Am not sure how the last would fit into a tree. Also lots of CUNNINGHAMs from OK who died in Tulare county.
Based on all this data, it appears a couple of approaches might be pursued.Obits often have info on relatives of the deceased.In the case of Ona, I believe Chavez Library in Stockton will do obit look-ups for a small fee if you provide CADI data.Libraries in Tulare county might do the same.
Another approach is to go for the "Records" available through the CADI and SSDI sites to see if they have additional info on her family.Believe there's also a fee involved there.Third, on occasions when I've been in Stockton, the library has old Directories that you can go through that have a lot of info in them .Do not believe library offers search of these.