How to select grandchildren of a page or category?

The functionality should be recursive all the way down to the last child. What is your WordPress version?

I’m using WordPress 4.2.1, the latest version.

Here’s my current setup:

Products Sidebar with Condition Groups:
– Pages (Automatically select new children of a selected ancestor)(Products)
– Categories (Automatically select new children of a selected ancestor)(Products)
The sidebar contains a tree of products

Page hierarchy:
Products (Sidebar OK)
–Caps (Sidebar OK)
—Male (4, 5, 6) (Sidebar NOT displaying)

Category hierarchy:
Products (Sidebar OK)
–Caps (Sidebar NOT displaying)

Were page “Male (4, 5, 6)” and category “Caps” created before or after you created the sidebar?

The “Automatically select new…” feature only works for new children, i.e. they have to be created after the sidebar is created.
If you want to select existing children for the sidebar, then you have to do it manually.

I see. They were created before the sidebar was created. Is there a way to program it so that it can include existing children? If not then I’ll manually add all of the children.

The feature has been requested before so it is already noted. The functionality itself should be rather easy to implement, but I have not yet found a way to give it a good UI/UX.

For now I suggest you add the children manually but still keep the setting on, so that new children are added automatically.