@sandgrubber
Most Guardian and Bully breeds it is visitors and strangers where you have these issue.
This is why you start training the day they come home and socialization as soon as the 3rd set of shots is done.

Clearly it sounds like this dog has had no real training.
Personally would start NILF training, and daily lead walks with a muzzle.
Also dogs will do a pecking order in a household.

IF ANYONE IS AFRAID OF A DOG. DON'T OWN IT. Dog sence your fear, and training will be next to impossible.

All dogs should start training the day they walk in the door, and it must be maintained.

Sorry to say if your family fears the dog and everyone is not ready to work on it, it is not the dog you should own.

It hard to express how much and how many of the posts in this I disagree with, so will not even bother.

The dog can't be fixed part though is 99% of the time bull, know of serveral people who have taken mastiff breeds and worked with them through fear and aggression issues, to have great stable dogs. And no these where not CM cases solved in a couple days, talking sometimes years of work.

That's a bit rude. Running a kennel doesn't give you special knowledge, but it does give you a different perspective than being an owner . . . or a breeder . . . or a trainer. . . or a veterinarian. And it's always better to know where someone is coming from. Btw. I haven't seen anyone claiming know everything?

Just how many "aggressive" dogs have you been involved with ? Just interested as 3 years ago you were the one asking for help & yet now you are the "expert" dishing out your advice based on your experience with dogs ??

If you look up Leerburg you will find a lot of useful training information that may help you.

For the rest http://leerburg.com/aggresiv.htm it is a good article I believe a few here should read.

Oh, hush. I never claimed to be an expert on anything. You love to be dramatic, don't you? Besides, three years is quite some time and my stance on biting dog in this household has not changed. Also, if you read, I said I had little to no experience with aggressive dogs, but I do believe that many people who call themselves dog trainers give out false hope with false promises.

JoedeeUK & mjfromga
How about calling it a rub, as neither is helping the op.

The dog was clearly not trained correctly and behavior issues where not handled when they first showed.
Currently I feel the posted is not prepaired to handle the training now required, that does by no means mean it needs to be PTS but yes most likely rehomed.

Yet so you advise using Leerburg methods to retrain this dog ?? HM he promotes e collars & other negative methods ??

I will say no more

You're right Lmost. I did not come here to argue, but somehow when JoedeeUK, Jackie, and I end up on the same threads, there is always bickering. Makes sense because we don't agree on anything and some people like to argue.

JoedeeUK, he did not advise she use those methods to train the dog, he merely said the article was a good read. Again, it simply seems you like to be dramatic. Just because a person is a bad trainer by your standards doesn't mean they are to everyone, and even if they are, it doesn't mean all articles featuring them are not worth reading. Goodness!

Re-homing a biting dog is such a bad idea. He will simply bite his new owners. You'd have to have someone who would agree to take in a dog that they know bites. Very hard to find. Like extremely. And most shelters won't take or adopt out dogs who have bitten. A dog this age that has bitten his owner is going to be near impossible to re-home, surely you understand that, right? If she can't get a behaviorist to work with her and the dog, the best option is likely to put him down imo.

As you have never had any involvement with the retraining of an allegedly aggressive dog, how can you even consider offering advice ?

When I was your age I was a Novice dog owner despite having owned my first dog(A working line GSDS bitch) from the age of 8(back in 1958 ) & having trained dogs for other people(not aggressive dogs), over the intervening 35 odd years I have learnt from some of the most natural of dog trainers(never got called behaviourizts back then), they showed me how without force, e collars, chokers etc etc They were experienced people who had been involved with dogs all their lives as had their parents etc. Since then I have helped with many so called "aggressive" dogs(many GSDs in rescue), have I failed ? yes twice with two dogs who had spent all their lives on chains, beaten, starved & never having any socialization(both were over 8 years old BTW)these dogs were so damaged that they had resorted to fear aggression to protect themselves & yes they were PTS & I have never been bitten by any of these dogs.

This dog needs to be assessed by a knowledgeable person, who has quality experience with dogs that have not been schooled in enough whilst younger. Paper qualifications mean nothing to me, I know many people who have extensive exams behind them & they couldn't train a dog if they had a million years to do so.

To the OP please seek out personal help, it is impossible to diagnose the source of a problem over the internet or the phone. Owner, dog & home situation have to be seen