Spirit is a Staffordfordshire Bull Terrier otherwise known as a ,"Pit Bull".
A Pit bull's genetic make up was developed so it would be a good fighting dog. However, this genetic disposition does not mean that all Pit bulls are aggressive or that they are prone to attacking other animals. Pit bulls require the same amount of socialization training as other dogs during puppy-hood, possibly more. Like any dog, a Pit bull that is well socialized is less likely to attack when it feels threatened.