This isn't about my dogs, but about my sister and brother-in-law's dogs. They have a chihuahua and a greyhound. The greyhound is huge. He can stand flat-footed and see what is on top of the kitchen counter. He is also harmless. His size frightens people sometimes, though.

The chihuahua thinks he is ferocious. He barks at anyone who comes to the door. The pizza delivery guy is extremely scared of the chihuahua. When he delivers a pizza, my sister and her husband have to go out on the porch to pay the guy and get the pizza. He is afraid to come to the door.