O, a cow is a cow and a pig is a pig and a cloud is a cloud. So sing two songbirds as they admire everything they see when they joyfully wing their way through a cloud-filled sky. And what interesting shapes those clouds are! As kids turn the pages and read the sweet, simple text, they will see the birds fly past wispy clouds in all sorts of surprising shapes. The Cloud Song, by beloved author Margaret Wise Brown, encourages kids to take a good look at the world around them and to let their imaginations soar to new heights.