The Sleeping Habits of Animals Bedtime! This is not just for children, but also for animals. But how do they manage it without a bed and a warm blanket? This non-fiction picture book for the little ones shows that there are very similar sleeping rituals among humans and animals: Otters may not have a warm blanket, but they wrap themselves in seagrass to avoid drifting away. Instead of dozing off like children on a long journey, frigatebirds take a nap while flying. And instead of pajamas, parrotfish wear a cloak of slime for the night.