954 Hi Jordan,
I wouldnt worry much about the other dog if there is no bloodshed. It sounds like normal interaction keeping the younger dog in his place while in her house. I would personally just keep them separated when they are eating and not leave any unfinished food on the ground. Pretty much follow what is in the “pack structure” section of the website (in the self-help section). It would never effect any future guard dog work toward people. If it was people holding down the boxer that would be a different story. That being said, your boxer is way too young to ever know what he is likely to do as a guard dog. The best idea you can get is if you know how his parents were. I wouldn’t even bother testing him until he is at least 18 months of age and mature. Being territorial or protective is mainly a genetic quality and less about training that you need to just wait out and see. The training part is mainly when you put a command to control on/off what the dog does naturally.