I've lost my copy of a function that would add up the same cell in every
other worksheet in a workbook other than the one on which I am using the
function..

Basically I have a grand total worksheet. Every other worksheet will have
values in an identical structure on which I want to get a total no matter
how many sheets are in the workbook. As I recall, it required the use of
Application.Parent.Parent to exclude the worksheet on which the function is
being used.

I need help in reproducing that function.