It is really sad that they can run loose and risk getting hit by a car. Do you leave in the country? If so, it's nicer that they get "free reign" of the area than to be kept cooped up all day in space too small for them. It would be nice if maybe your neighbor could keep them in a fenced area with a pond of their own, but that would be too perfect, probably. If you are this concerned, maybe you should go have a friendly neighborly chat with him (sans your son and your anger) and discuss how worried you are about the ducks and geese? Who knows, maybe he'll come around.