I just discovered more information about this picture! I've had it for many years and today, for the first time, found some writing on the back. It is barely visible, but in bright light with a magnifying glass I read a key to the numbers on the front. (1) Nancy Alva Moore Dyess, as I said before. (2) Hattie Celeste Moore Butler. There is also "No.5" written on it and what appears to be letters below that in what looks like might have been a stamp at one time. The first letter appears to be a "T" but that's all I can make out with the naked eye.
Ada was Robert Lee Moore's sister. If the date on the photo is correct, the wagon train photo was taken before 1890, which seems plausible based on the ages of the identified children.
My great grandmother, Nancy Alva Moore Dyess is the little chubby girl in white sitting on the left. Her mother, Sarah Jane Knox Moore is the lady sitting to her right in the dark dress. Sarah is Robert Lee Moore's mother; Nancy Alva is his sister. Foster Alonze Moore, Lee's brother, is the small boy sitting up on the wagon. I have not identified the rest of them. I'm fairly certain Lee and Nellie are in the group, just haven't taken the time to compare pictures. Based on my great grandmother's and Uncle Foster's apparent ages in the photo, and the fact that Sarah Clementine [their sister] died in Bell Co. in 1896, the closest I've been able to figure is sometime between 1887 and 1896. I'm still gathering information to get a closer date.
I have no idea. If it is the Robert Lee Moore mentioned earlier, the date on the stone could have been an error. Although that would be a pretty weird error. But it's definitely not Uncle Lee.