I did a little more looking, just for fun, and found Aaron in the 1900 census under the name McKeen. In 1900 he was still living with his family, at 1900, Georgia, Walker, W. Armuchee, E.D. 98, pg. 1A. His older brother John was head of household, and his widowed mother, Sarah, and three siblings were living with him. He is 25 and single. Therefore, he must have married both the first and second times between 1900 and 1910. Since the 1910 shows that he married Carrie around 1907, he would have had to marry Kay between 1900 and 1907. I couldn't find a Walker County Georgia marriage record for him even though he lived in Walker County from 1900 to 1920. Good luck.