This is a dominance issue. He accepts you as the alpha & pack leader but he is challenging family members and succeeding.
He needs to learn his place in the pack is dead last period & PRONTO! (Ok the cat if you have one can be dead last LOL!)
I am sure there are many here that will disagree with what I am about to post next. So be it.
I am not going to sugar coat this problem. I am not talking about appropriate aggressive & protective behaviors towards strangers or people that are a threat. We are talking about Dobermans not Pugs here. I have a N.A x Euro cross because I think most NA breeders and the AKC have lost sight of the fact that Dobermans were bred to be protection dogs.
If you want take the lovey dovey warm & fuzzy training approach to dangerous behavior thats your call and when somebody gets hurt and animal control officers come for your dog thats on you.
I believe in positive reinforcement & positive training methods as much as anybody.
But this is serious business for all involved. It's dangerous for both the family and the dog .
Dogs that hurt innocent & non threatening people end up getting destroyed and their owners sued.
This a behavior I simply do not tolerate.
Showing any form of aggressive behavior towards me or any family members is at the top of my list of things I don't ever let my dog do.
I don't care if it's a baby, small child or my great-grandmother.
I never let any of my dogs get away with threatening any family member, not even once.
I make no apologies for my "No one.. yet alone my dog threatens me or my family ever!!" position on this. Man or beast no different in my book. I love & protect my family and my dogs are family to me.
If they do I respond in such a way that they will never do it again.
It will be immediate & a very unpleasant lesson..as it should be.
I am a big guy 6'2" 250#s
On the very rare occasions my dogs have tried this in the past
(After 40+ years & 6 dobes of my own and fostering
more dobe rescues than I can name .)
It has happened only 3 times... 2 were males around 8 & 10 moths old and a 15 month old bitch that we fostering for a rescue.
(Note) If you are not 100% confident in your role as alpha & pack leader call in a professional that is. If the dog does not respect you as alpha you will get hurt.
I handled it this way...
I grabbed them by the scruff of their neck (Just like an alpha wolf does) pinned them on the ground. Grabbed them by their throat and made myself as big and scary as I possibly could.
I looked them directly in the eye and literally growled at them as loud as I could.
When I let them go I chased them off into their safe space AKA their crate. And gave them time to reflect on what just took place. After they processed what just took place all of them came to me exibiting very submissive behavior. I petted them and the lesson was over and done.
It was not an experience that they ever wished to repeat and they never did.
My actions were proportionate and age appropriate.
I don't respond to a 8 month old doberteen the same way I would to a full grown dog.
And yes there were some pretty over the top theatrics involved.
Just like when I am playing with a small puppy and they get a bit too rough and bite a little too hard.
I will yipe, yelp ,cry and "act" like they really hurt me. They always respond with a "I am sorry behavior" Give me kisses and then play gentle.
As I stated in the beginning this is a dominance problem in your pack/family and I am not going to sugar coat it.
You as pack leader let a member of the pack bully & threaten another member of the pack.
That was a failure of you as alpha and pack leader. It is your resposnability to protect everyone in your pack/family.
Learn from it.
I will close with this..
If one of your children pulled a knife or weapon on another family member and threatened them with serious injury would you allow it?
Or would you take action the moment it happened and make it crystal clear that that is never ok and will never will be allowed...EVER!
Would you allow somebody else's dog threaten your family members?
If not, why are you letting
your family dog do it?
I know my post won't be popular or agreed with by many here and that fine.
It's not politically correct in this age of micro aggression & safe spaces.
I don't tolerate canine terrorist or 4 legged wrecking balls in my pack/family.
And for the life of me I don't understand why anybody does.
Be a loving but firm leader and your dog will trust, follow and love you for life.
Good luck!
MR
PS For those reading this that think I am some big ogar that likes to be mean to my dog to prove what a tough guy I am. Here is a photo of Maja and me in my bed taking a nap after a trip to the park. As you can tell she doesn't love or trust me. LOL!
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