You might be surprised to hear that some people sleep with their eyes open. And it’s more common that you’d expect. About 20% of people do it, including babies. Doctors call this condition “nocturnal lagophthalmos.” If you have it, you can usually close your eyes most of the way when you sleep, but not completely.
Unlike regular calls, the receiver does not incur charges to receive the call. But for WhatsApp, both parties pay data charges to call and receive a call. It is important to know which network you’re using for the WhatsApp call so that you won’t be overwhelmed when you see the bill.