there is a reason they say let sleeping dogs lay. it is definitely not an unheard of behavior but first make sure there is not a physical reason for it like pain with a vet visit. then you need to manage where the dog is allowed to sleep.
Sleep startle in dogs
Like all animals, a startle reflex is a dog’s brain and body’s way of helping protect them from potential danger. Sleep startle is also sometimes known as sleep aggression and occurs when a dog is woken up suddenly or unexpectedly. If a dog has been woken up by their brain telling them they’re...