How did we get from people calling themselves night owls to people suffering from insomnia? You do realize that these are different things I hope? If not, her

How did we get from people calling themselves night owls to people suffering from insomnia? You do realize that these are different things I hope? If not, here is a hint: a "night owl" has no trouble falling asleep when it's "their time" to sleep. A person suffering from insomnia still struggles to fall asleep even if it's 2am.