Mara Noia

This plugin adds a “create new sibling” and a “create new child” button on the page edit page. 
This way you can easily create a new sibling or child directly from the active page, without having to choose the parent.
Further more you get a list of siblings of the current page, to make it fast to switch between editing siblings.

Mara Noia Extended Page Actions

When administrating your pages in WordPress this plugin can speed up productivity.

adaptsites

Kegan Quimby

Communicate and collaborate by leaving sticky notes on any page of your site. Drag and drop them anywhere you’d like, type a note, and change its color/priority.
This plugin is a fork of StickyNotate https://wordpress.org/plugins/stickynotate/
Here’s how it works:
<ul>
<li>While signed in, go to any page on your site</li>
<li>Click the Add Note button in the admin bar at the top of the screen</li>
<li>Click and grab the top of the note to move it anywhere on the page</li>
<li>Type your note text</li>
<li>Click the save button in the lower right of your note to keep your changes</li>
</ul>

Site Sticky Notes

Add sticky notes directly to website content.

Mara Noia Extended Page Actions vs Site Sticky Notes