A jealous dog is not always possessive or protective. It is your task to figure out what’s bothering your pet before you can deal appropriately with the behavior. The distinct behavior of possessive dogs – growling, snapping, whining, or attacking a person or another pet – reflects his feelings of insecurity, confusion, and a lack of confidence. These negative feelings keep him always alert and on-guard, which can eventually stress him out. When he is teased, his display of aggressive behavior is a form of protective mechanisms, because in his mind, his owner is not giving him any protection. For these dogs, aggressive behavior is a serious issue that should be dealt with ASAP. Any form of aggressive behavior should be brought to the attention of your veterinarian Staff because it may also be due to medical issues affecting your dog. In serious cases, the help of an animal behaviorist may be needed to deal with the dog’s possessive aggression.