My dog purrs you know. He does - honest. It's not a growl-ie sound - and he's not whining - it's more of a gentle mmmmmm sound.
He does it mostly when he's really tired. He snuggles in for a cuddle and rolls over for his belly rub - and purrs. He also purrs when you rub his ears.
Of all the dogs I have ever owned / trained / cared for / looked after - Fidget is deffinatly the soppiest.
Yours with snuggles