my mother has a twelve yr. old trisenja name Trey. He's a very people oriented dog, but has recently had serious territory and food aggressive behavior. We think he might have a thyroid problem. We already lost his sister to dementia, so now in the vacuum of her absence, he becoming more unpredictable. I recently moved back into my mother's house with my family (wife, step-daughter in 4th grade, a 3 yr. old lab, and two cats(the cats really don't figure in to the equation, since trey already know not to mess with felines, he's curious but backs off.) originally his sister was the main problem, she had become violently aggressive towards everyone in the house to the point none of us could handle/train/play with her or be even in the same room. And now his behavior is just getting worse. He's bitten my wife several times, usually when she is correcting him, or when food/treats are involved, or randomly when his neck is touched. She grew up breeding/training dogs, and she has run out of options of training him and is now terrified of trey. we've sadly lost one dog to dementia, I really REALLY need some help to save my dog.