I am here on behalf of my brother. We are both senior citizens and roommates. He owns a German Shepherd about one year old. At night when I enter the kitchen, (which is near my brother's room where "Abel" is, he'll jump up and bark at me. He knows me very well, we get along fine all day long, I give him treats ( but don't over do it ). Anyway, at night, when I'm raiding the kitchen for some reason, he gets real protective of its owner, my Brother. My brother doesn't know how to get him to stop barking at me. And he'll only jump up and bark at me once or twice, and that's it. It's not a continues bark, but it wakes up my brother. He doesn't bark at me at any other time. We live in a mobile home park, and my brother ( who is partially handicapped ) will do yard work for other seniors, and he'll take Abel with him, and Abel barks at other dogs. So, we want him ( he's a male ) to stop barking late at night when I enter the kitchen ( again, he doesn't bark at me any other time, and he allows me to be affectionate, pet him, etc ) and to stop barking at other dogs that are being walked going by. So, the question is, do any one hear recommend an anti barking collar, or device, and, if so, ( not talking about shock collars, no way we'd do that ) just the kind that give a high pitched sound that humans can't hear, but dogs can. Do these work? There are many for sale on Amazon, some with good reviews. Any one here can give advice that would be nice. We are poor, and cannot afford a professional trainer.