Disambiguation
When different pages with children have the same title, referencing the relevant grandparent in the children disambiguates which page is intended.
- Page A has a child page with title C, and a grandchild page with title D.
- Page B has a child page with title C, and a grandchild page with title D.
- The grandchild pages specify their parent and grandparent pages, so there is no ambiguity.