Illness or physical defects also affect a dog's behavior. Still, a dog's basic inherited temperament, instincts and training are what have the biggest effects on how and why a dog reacts to what is going on around him. Dogs that are not mean or aggressive by nature sometimes will react when they are teased or frightened, when they are in pain, and when they feel their territory has been invaded. No matter how much we love our Saints, we must realize that they are animals and they must be treated as such. It is essential for us to understand that almost any dog will bite under the right circumstances.
Parents can avoid confrontations between dogs and children, and can nip problems in the bud early.
The following suggestions can help. Teach your St. Bernard basic manners from the day he comes home with you. Never leave your St. Bernard alone with a child under the age of five. Not in the house. Not in the yard.