Alexander, a second welcome to Rootschat.
My family also come from Johnstonebridge and whenever I am heading up or down the M74 I usually stop at the churchyard, which is now very quiet and undisturbed down by the river. The churchyard's position is uncertain as the church building has been deconsecrated and is for sale. A couple of years ago I met a young man there who was thinking of buying it to convert to a family home - he said families would always be welcome to visit the graves, but it looks as if that never happened and each time I visit it just looks a little more sad and overgrown. Many of the gravestone inscriptions are very clear though and I can't imagine access will ever be denied.
As agdhadowey says, you need to give us a clue around timings to start with - with the variety of ages and people on this board, 'great grandfathers' can vary from appearing in the records in the 1840s to being born in 1920s!
If you have nothing specific on Wiliam and Jane, then what do you know about your grandparents ages, even roughly? Identifying the birth of William and Jane's child, whether your grandfather or grandmother, will help take us back to William and Jane themselves. Just be careful not to post details of anyone who is still alive.
