dainius.kaupaitis

When navigating on pages widget shows links to child pages. If there are no child pages – widget shows „brother“ pages. 
Link of currently viewed page can be styled through CSS. Widget shows nothing if user is browsing Posts (not Pages). 
Admin can configure:
<ul>
<li>widget title</li>
<li>which pages must be excluded</li>
</ul>
Widget can be localized.

DKA Child pages widget

zweidesign

This WordPress Plugin transforms children pages into OnePager sections of their respective parent page.

OnePager for WordPress

This WordPress Plugin transforms children pages into OnePager sections of their respective parent page.

DKA Child pages widget vs OnePager for WordPress