Hi Richard, This is what I found according to the 1920 Comanche Co., OK census:
1.Ona is listed as Ina Harrity, age 23, living with her parents in Lawton. J.W. Phipps (63) and Anna (Hollingsworth) 64.Your mothers name is listed as Catherine Irene, I think age 5.The writing was not to good.John Harrity is not listed and he was born in PA.
2.J.W. Phipps was born in IL and Anna Hollingsworth in MS.
3.Thomas Phipps is listed as age 28 with wife Gayle (can't tell the age) and daughter Anne, I think 1 1/2.
This is also a J.O. Phipps age 25 that could also be a brother, but I couldn't tell where he or his parents were born.
I hope this helps you out a little bit.My grandfather was also stationed at Fort Sill in the mid/late 1920's.My dad and two aunts were born there.