Invisible threat

It has been said that a dog's eye is different than man's. Their vision to see into the blackness of night and pull out images that would be invisible to a human. There was once a dog, a very unassuming dog. She would be considered normal by standards. Loyal. Friendly. But she was quite peculiar. She had a special sight, to see beyond the pale of shadow. To catch the images of ghastly creatures that loom just on the fringe of reality. Hoping to breach their realm into our world. Only through a resting and dormant mind can they cross. And so they wait until the sun drops low in the horizon and sleep calls out to the family, begging and inviting them to slumber. When their eyes close, the door to the nether opens ... just a crack ... but wide enough for the evil to enter. When the dog's eye catches the movement of the creeper attempting to cross, the howling and barking begins. Stirring the family from sleep. And although never abused physically she takes their scorn of verbal anger. Why won't she let them sleep? They would curse to each other. But if she allowed it, they would surely be lost.