Thank you so very much for this information, MWS. It will be the correct couple. The 'Alice' was my father's aunt. Her brother, (my grand-father (I'm now 74)) - was John Darby Stafford. Their mother was either Joyce or Marjorie Darby. I presume now it was 'Joyce'.
Joyce died young, and Alice was brought up by her Darby grand-parents. My Dad, John Stafford visited his aunt only once, since his parents had separated, but he said that their son died in a motorcycle accident while he was there (must have been after 1918 - he was born 1911). - and the body was laid on a table. I think the boy must have just been injured, as - as you say - the boys were hale and hearty until the 60s and the 90s.
I have been trying to piece together my family's Brummie roots, MWS, since my father was brought up in Scotland, and due to his parents' separation, we were never told that the Staffords originated from Kingswinsford and Cradley Heath, and Rowley Regis. What area do you come from?