Need to have multiple project versions appearing within one project

To my knowledge this functionality does not exist.

I have one parent project with sub-projects underneath. The sub projects have their own releases which may align with (and be part of) the parent project ... or they might have to release mid-stream.

I need the ability for each project to have their own versions (for Agile planning) but also be able to have the parent project versions selectable on that projects pages.

Sub project page
*Sub project version
*Parent Project version

Essentially I am just trying to tie all sub projects into a parent project so when the parent is ready for release...we can run a search that says which stories/defects from the sub project made in to the parent release.

I know the Multi-Project Picker Custom Field allows users to assign a project to multiple projects...but does it allow to show which version of these releases the story will be in? Or just list multiple projects?