For podcast management I am using iTunes of course. I like iTunes. Really!
Sometimes my fingers are too fast and something is trashed, especially podcast episodes. If you are wacking the same as me, then I am sure this or the other time you want it being undone.
Of course there is a simple and quick way:
Just select any episode or the podcast itself, then hit on the bottom left the unsubscribe button. Then it turns to subscribe, and press it again. Then iTunes will reload the feed and you can download the lost childen, again.