Speaking of cats as we were - 20-something years ago my friend's vet put her fat cat on a diet - just less food, I don't remember any fancy stuff. The skinny cat who was a picky eater started meowing under her feet in the kitchen so was given treats - for a while, until my friend noticed skinny cat was pimping for fat cat! I also don't remember if the meowing continued as a duet, or if there was silence in the kitchen.