I have 3 German Rotties, all are 1/2 sisters (same mom) of different ages. We actually had one that passed away a few years ago and we got the last puppy of her mom's last litter to bring our collective back to up to three. The father's are flown in from German each year to stud the moms. German Rotties are slightly different than American Rotties which are bread more for looks than strength and work ethic. I only have female because males are much more aggressive defenders of the "territory" while females are much more aggressive defenders of "family". That is possibly because they take on a maternal roll with the children.
First and foremost are dog's are trained to be obedient. Obedience is everything with a strong dominant breed. It is also essential that this obedience goes beyond just their primary master, but to all family members. And it's not easy to get to that place. Everything they learn has an obedience component. Next we immerse them in love & affection from the family (especially the children), along with special treats for pulled ears, grabbed noses, accidentally pokes, etc. Once the dogs see the kids as family who's accidental whisker grans result in treats, we start to socialize them to some extent. They need to learn that if we invite someone in that is very different then if someone just comes in. That if we encounter another animal, they are not supposed to automatically attack it and never to just run off because they see something fury. That brings us back to obedience. Next we teach them to stay on our property (fence or no fence), never to take food from anyone other than us, to bark or growl and show teeth on command and to stop on command, to always position themselves between the "stranger" and a family member, to cease and desist any aggressive action upon command and that "come" means right here and right now.
So basically if you want to rob our house, put together a team of criminal toddlers with pockets full of pieces of fatty red meat that can beat both a monitored security system and video surveillance.
Of course it is also important to have a smart dog with a good personality. We actually re-homed a Rottie once some years ago that just did not seem to take to the training. We put in 2-3x the time and effort and only got 1/2 the results. The kids were not happy, but I am not going to take any risks.
