"Swim" little ducks went out one day. Over the hills and far away. Mother duck called, "Come back, you kiddos! It's becoming dark." But only four little ducks came home that way. Where's your sister? asked mother duck https://www.youtube.com/watch?v=58WVXwbYsDs&pp=ygURZml2ZSBsaXR0bGUgZHVja3M%3D