Your son is too young to exercise dominance over the dog, so the dog won the prize. (samthedogtrainer.com)
A May 2009 issue of the Journal of Veterinary Behavior highlighted a study that indicated human attempts to assert dominance over dogs tend to increase canine aggression in return. (brightdog.com)
Michael taught us patience, yet firmness, using rewards / positive reinforcement methods (as opposed to negative based use - of - force methods to establish dominance over our dog, as suggested by others). (michaels-pack.com)