Formula That Will Allow Me To Extract Date Range From Sub-Group

Here is my example:
I have 5 parent-level Campaigns.
Each of those parent-level Campaigns contain two sub campaigns
Each of those sub campaigns have unique start and end dates.

I want to see, in descending order, the date ranges of those start and end dates attributed to the parent-level campaign.
A pivot table will not allow me to do this and I wanted to see if a formula could.