Getting parent slot content


I am trying to display the contents of a parent slot only if the current slot is empty. I have read through a number of threads regarding this issue but cannot seem to find any thorough answers. There is a mention of the ‘reverse content finder’ but there appears to be no documentation on this? If anyone has a descriptive fix for this i would be very greatful.

Thanks in advance,


I managed to get this working using the node macros from this thread: