From information found on the 1920 and 1930 federal census records, it appears that the parents of Gladys Sanders were Ralph Sanders, b. abt. 1896, and the former Maude L. Pugh, b. abt. 1898 in Alabama, the daughter of Jasper N. Pugh, b. abt. 1870 in AL. There seems to be some confusion as to where Ralph and his parents were born. The 1820 census states he was born in Arkansas, his father born in CA and his mother in MO. The 1830 census, however, appears to say he was born in AL, his father in AL and his mother in AR. It also appears their firstborn child was a son named William R., b. abt. 1918, who was deceased prior to the 1830 census.
Here is a brief summary of those records:
1930: Liberty Hill Twp., Dallas Co., AL.
Ralph Sanders, 34, AL AL AR, logging & shipping.
Maude L., wife, 32, AL AL AL.
Virginia, daughter, 9, AL AL AL.
Gladys, daughter, 7, AL AL AL.
John W., son, 3, AL AL AL.
1920: Awin Twp., Wilcox Co., AL.
Ralph Sanders, 24, AR CA MO, farmer.
Maud L., wife, 23, AL AL AL.
William R., son, 1 yr. 9 mos.
Jasper E. Pugh, 19, brother-in-law, AL AL AL.
In 1920 Ralph and Maude lived nextdoor to Jasper N. Pugh, 50, widowed, AL AL AL. His children (Maude's siblings) were:
Elna M., 24,
I hope this helps get you started. I also hope that your line of Sanders kin is easier to research than mine.