No comment on the artist , as I have not knowledge of the sig , nor researched it , but I do believe that I may have stumbled across the obvious , regarding both paintings you've posted here .
By the general structure of the facial features of both paintings , I think these two might just be the same "R. Johnson" , at opposite ends of the age-scale .... his own personal 'portrait of dorian grey' as it were .
Serve me up a heaping plate of crow if I'm wrong !!!