wp_list_sub_pages will list only pages within the same category (top-level parent) as the current page.

Didier Sampaolo

This WordPress plugin is oly one function. It takes exactly the same parameters as wp_list_pages, except for child_of, which is used internally. 
When called on in template file, it will list : 
* on the homepage of the blog, every page and subpage (default, this can be overriden by parameters) 
* on every other page, only the pages with the same top-parent (parent of level 1)

Alternatives to wp_list_sub_pages

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