The two owls from Darnassus and the mechanical squirrel came at around the same time, not sure which was first.

I had several copies of the same pets from different toons, putting my total over five hundred, so I had to cage many (usually keeping three of the same pet), and 'release' many more (oh, look at all those balloons flying away!). I sold a few, but I don't think they'll all sell. I don't think Blizz ...