Rob & William Kuykendall
This is William and Robert Kuykendall. They are the sons of James E. & Frances Tyson Kuykdenall. Robert is the one with the Groucho Marx lenght coat on.
I don't know, but I suspect the pictures were taken about the same time with the same photographer. There is a certain style the photographer (s) conveyed in both portraits, sort of like Butch Cassidy and the Sundance Kid.