Latest posts of specific cat in sub menu area

[hedu]

Dear forum,

the title of this thread is a little short, it should be:

"How to display the latest posts of a specific category in the sidebar within a specific sub menu area only"

I have to create this structure:

page 1
- category 1
- sub-page 1.1
- sub-page 1.2
page 2
- category 2
- sub-page 2.1
- sub-page 2.2
page 3
- category 3
- sub-page 3.1
- sub-page 3.2
and so on

Now I need to display the latest 3 posts of category 1 in the primary sidebar on

• page 1,
• category 1 (and all its posts)
• sub-pages 1.1
• and 1.2 only.

And similarily I need to display the latest 3 posts of category 2 in the primary sidebar on page 2, category 2 and sub-pages 2.1 and 2.2 only.

I think about using the plugins "genesis featured widget amplified" for showing the posts of a specific category, and "widget logic" for displaying the widget only when I need.

A quick test involving a PHP variable generated in functions.php, and using it with widget logic, works perfect.

Remains the question how can I know that I am currently on page 1, OR on cat 1 OR any posts in cat 1, OR sub-page 1.1 OR on sub-page 1.2? These items are grouped within a custom menu. Or in other words: using which algo can I set the value of my PHP variable in functions.php?

I would need e.g. a function like get_ancestors_in_custom_menu() returning an arry of IDs, which does not exist.

What could I do? Is there a solution by far better than mine?