Herding dogs herd. Guarding dogs guard. Terriers dig. So, when your herding dog nips at your children’s heels, he isn’t being aggressive. Your herding dog needs training and lots of exercise. When your gentle dog, bred to guard his people and possessions, barks aggressively at the neighborhood children running around your house, he isn’t acting out of character. Separate him from the children and appreciate that he is a good protector of your family. And that terrier that you thought was so cute may seem less appealing now that he’s digging holes in your yard. But his job was to dig for gophers or other vermin. Instead of getting frustrated with him for doing what he was bred to do, teach him to dig in a particular area by hiding toys and treats in soft soil or sand.