A loose big dog can be intimidating to anybody, even the most ardent animal lovers, unless of course they personally know the dog and that it is friendly. My advice is to go on walks with Lady and let her meet and greet the neighbors. Once they get to know that she is friendly and will not harm them, you will find the attitude of the neighbors to be dramatically different. I certainly wouldn't take offense at your neighbor coming over to voice his concern. After all you know Lady's demeanor. He doesn't.