My female thinks she's a guard dog. Whenever she hears a car she doesn't recognize pull into our drive, she starts to growl at it just like our dogs used to do. Maybe she is taking over their guard duty as we don't have any dogs right now. She doesn't have the courage to do anything but growl. If the person gets out of the car and comes to the door she tears off for a hiding place. But she's all tough until then.