I was reading and singing the book "The Old Lady Who Swallowed a Fly" to my daughters. I asked my daughter if she would swallow a fly, and she said no. I asked her if she swallow a cat, and she said no. My son who was sitting nearby playing with Lego's said, "You can't swallow a cat. That's nasty. If you do it will go poo-poo inside of you, and that is nasty."