Yellow Bird shares an ordinary button that does nothing with Red Bird and Blue Bird, and they are delighted to find that pressing it makes them happy, which is something., "Yellow Bird has found a button and wants to share it with Red Bird and Blue Bird. This is just an ordinary button. It does not do anything when you press it. But when Red Bird and Blue Bird give it try, they are delighted to find that the button does not do nothing, and that is something!"--