Besides insecurity and jealousy, the Miniature Schnauzer in the video was likely never properly socialized with other dogs before it was adopted into the family. To prevent bullying among dogs before it starts, dogs need to be properly socialized from an early age. That way, they can learn to understand and respect canine body language, boundaries and how to be a respectful playmate. Besides the methods recommended by the trainer in this video, canine experts and veterinarians also recommend using another dog that can tolerate the bullying dog's antics. Allow the two dogs to interact but watch them closely. If the bullying dog behaves properly, praise both dogs. However, if the dog displays the problematic behaviors again, calmly say "time out" and remove the bullying dog from the scene. The goal is to pair the trigger phrase with the end of play time, but not in a negative way. That way, the bullying dog will learn that if it wants attention from others, it'd better calm down and behave properly. That said, the couple can also enlist the help of the calm, cool, and smart Border Collie to improve the Miniature Schnauzer's behaviors. 😄 But, of course, they should use the methods recommended by the dog trainer first - those methods are easier to implement than involving another dog in the procee.