I would guess the date range to be 1910-1940. In this one, our great grandma, Annie Lou Stewart Thornburg is in the middle. I think this may have been taken at Jack's funeral in 1937. My grandpa Jim is on the far right. I'm 99% certain that Mary Anne is the petite girl with dark hair.
​L-R:
1. Stella Thornburg ???
2. Josephine Thornburg Martin ???
3. Roy Thornburg ???
4. Lee Thornburg (hidden) ???
5. Annie Lou Stewart Thornburg
6. George Thornburg ???
7. Mary Anne Thornburg
8. Nora Thornburg Irons ???
9. Jim Thornburg​

I agree that Mary Ann is on the right, Stella is in the print dress on the left, that could be jo next to her, but don't think so. Mom had that fox stole in her cedar chest, it probably was Stella, but that picture doesn't look like her. Molly

NoraMaryAnnAnnieLouLeeRoyStellaJoJim