Diana - Thank you for pointing out the other cemetery in Stoneykirk. I shall try and contact someone (not sure who!) in Stoneykirk to see if she is buried there, it looks more than likely.
Allan - Thank you very much for the photograph of my grea-great-great grandparents headstone, so appreciated!
The last stumbling block remains the burial location of William & Sarah Gibson.
They both died in the late 1930's, in Inch, but aren't buried in Inch New Kirkyard - does anyone have any suggestions as to where they could possibly be buried?