If our cat was a cow...

Posted by Joris De Roeck on May 07, 2007

If our cat was a cow, we could milk her behind the stove.

It's the translation of a Flemish saying, and I wondered if there's an English equivalent (I could really use in a lesson I need to give next week) The meaning is something in the style of "After things happened, you could wish that they went differently, but that's all vain whining".

I would greatly appreciate any help you can offer.
Already great thanks