Not sure that the one I found above is right. There is a site if you google Seherford devon, came up with census for 1841 sherford, which has a William 65 a thatcher, widower I think, no Mary plus various others which could be sons, George 34 William 40, and grandchildren.
The one I found on my first posting is in a different village with a Mary, but Mary is not on the Sherford census with the William there.
We need to find the 1851 census for Sherford to see if William there in 1841 is still there.
also find the burial of Mary, should be in Kingsbridge reg area, if she died between 1837 1841.
If