Dolphins sleep with half of their brain part of the time, and then switch over to the other half, always moving. Even fish sleep. Guppies have stripes along their bodies. It's like the fish are changing from pajamas into clothes. Bats sleep upside down.
Leopards sleep on tree limbs without falling.
Penguins sleep standing up in circles with their backs to the wind, taking turns on the outside to permit those in the middle to sleep. Gentle water colors by Sari O'Sullivan show a wide array of dozing animals. Good night, sleep tight. And so, at last, does Mahla.