Your relationship to the person on whom you are spying matters. If that person is your child or your employee, you have a lot more leeway when it comes to monitoring their activities. If you think someone is spying on you illegally, file a report with local law enforcement so they can investigate your case.
Most cats snooze around 16 hours per day. The majority of their sleep time, however, is much shorter than the typical seven hours or so that humans average at. night. Cats tend to sleep lightly, without going into a deep sleep.
You should keep your cat away from babies or small children so your cat does not attempt to lay on them. Cats may also sleep on your head so they are easily awakened when you wake up. Cats sleep for about 16 hours/day but they are usually awakened quite easily.