Mastin Hill?

this is a picture that is supposed to be a man called Mastin Hill. He was married to my great-aunt grace markley in lawrence county, missouri on the 29th of augest 1917.he was supposedly killed in a construction accident a year or two after they were married.I would like to find out if this is indeed mastin Hill as my grandma had the very same picture and would never tell us who it was. if it was her sister's husband , why not tell us that. It wasn't till i found Grace's grand-daughter online that she sent me the picture that matches the one I had, and they mystery started.If anyone has any information about this man please let me know

this is supposedly a photo of my great-aunt's husband mastin Hill. they were married augest 29 1917 in Lawrence co, Mo.My grandma had the very same picture and would not tell us who he was, it was only when I met grace's grandaughter on-line and she sent me a copy of this picture that I knew who the man was supposed to be. I would just like to know for sure who he is so my cousin will know he is her grandfather or not.