The golden rule with dogs is to deal with unwanted behaviour as soon as it appears. Do not tell yourself it will improve over time- it never does, left unchecked it always gets worse.
In my work with aggressive dogs there is always a behaviour pattern that emerged long before the dog became aggressive. Jumping up, possessiveness, fear, nervousness, excitable around other dogs these are all early signs that should be heeded.
Just like children dogs need leadership and guidance and the sooner you deal with a problem the easier it will be overcome.
Balanced and well-adjusted dogs never wake up one morning and decide to attack. Dogs that do have been sending signals they need help for a long time.
The old adage ‘He’s never done that before,” following an attack may be true but you can bet the dog has been showing signs of aggression for a long time except no one was listening.
Dogs can’t talk so they communicate with body language and actions. If your dog is behaving inappropriately do something about it now and help him become the happy balanced dog he really longs to be.
NB: Do NOT deal with aggression problems without the help of a professional.