Link Pivot Item Question

We have a workbook with what the users call the 'main' tab. This is nothing more than a pivot. There are two other tabs in the workbook, they call them the 'detail' tabs-again just pivots. Each of the 3 tabs has one item in the page area: MONTH. The users want whatever MONTH is chosen on the *main* tab to be applied to the *detail* tabs. In other words they just want to select MONTH once and have the 2 ancilary pivots filter to whatever the user chose on the main tab.

How could I do this without using a form? Could I post some sort of vba code in the view code area of the main tab? What would it look like?