I notice in your message history you mention Ethel Campbell Cook was orphaned and taken in by another family, would they be named Wilcox?
On 1910 census Martha Wilcox, Stepmother, 66, wid, b AL, AL, AL is living with J.O. and wife Ethel.Since the parents of J.O. are living next door to him, I assume Martha is actually "stepmother" to Ethel.
On 1920 census Martha Wilcox is again living with them, now listed as mother-in-law, 75, wid, b AL, AL, AL.