Unless your pages are arranged in folders that mimic exactly the logical layout of your pages, then no, you can't do it - there is no requirement that "this page must be a parent of that page" and nothing to enforce such a relationship. A page can be accessed from a huge number of other pages even within the same site.
If you do arrange them in folders - which would be unusual - then you can probably get the relationship from
request.PhysicalPath[
^] and parsing the string it returns.
But probably, you are trying to do something a bit odd and it is unlikely to work exactly as you expect. What are you trying to achieve by doing this?
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