If it is the Bradley/Openshaw marriage, there do not appear to be any births after 1911 in County Durham.
Did they move away to elsewhere in England? (Just trying to pin them down)
Also, have you either of them in 1891 and 1901, and got death dates for them - have you identified their births?
Thanks
Added:
I cannot see a Mary Openshaw born around 1885 in County Durham, so is it just Robert who is from there?
However the only Robert born in Durham in 1885 is Robert William, and the marriage is just of Robert.