[REQ] show picture located in a sub-category also in a main-category

[TIMT]

Hi everybody

I have the following category-structure:

Architecture (1)
Photo Clubs (2)
    Photo Club A (3)
        Architecture (4)
    Photo Club B (5)
        Architecture (6)

I'd like a new field in the table category. In this field I can define other categories.
Let's say I enter on the category "Architecture" (#1) the sub-categories  "Architecture" (#4 and #6)

Now I see in the Main-Category (#1) all picture out of the defined categories (#1, #4, #6).

That new features is important for me. So has each photo club his own categories, but the pictures are also shown in the main-category.

Thanks for helping me.

TIMT