How can I get all children posts regardless of parent.
If you require more info:
The setup I have is like this: I have a custom post type "Project". I will create top level pages as the "main" project page. Then I will have children pages as something like a project blog. Mainly for WIP posts.
I will have a Portfolio page that shows all completed projects, and a "WIP" page showing all WIP posts regardless of project. How can I do this