pagination – Find out how to paginate by youngster and grandchild pages (present code solely works with youngster)

I need to paginate youngster and grandchild pages of a mother or father web page. My code works, nevertheless it skips granchild pages and goes to the subsequent youngster web page. How can I alter this code to additionally embrace grandchildren?

1. Guardian web page
2. Little one 1
3. Little one 2
4. Grandchild (youngster of two)
5. Little one 3

On Little one 1, I would like “next” to go to Little one 2, and nothing as “previous. On Child 2 I want Grandchild to be the “subsequent.” On Grandchild, I want “subsequent” to be Child 3 and “earlier” to be Little one 2.

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