kathb on Family Tree Circles

am looking for Hugh owen, my great grandfather, but he's a bit of a mystery man. He had a family in Belfast Northern Ireland prior to WW1, however I don't know his wife's first name or her maiden name. By the 1920s 04 1930s he was, so family legend says, dead in some sort of accident and buried in Sheffield. Just wonder if anyone has any ideas for finding out where he is buried.
Also trying to find out about Joe Mills who also settled in Belfast, believe that his first wife was from Omagh and she died fairly young. Joe remarried and had more children with his second wife.