I had to chime in. I had the same / similar situation. I told my neighbors repeatedly that I did not want their chickens free ranging on my property, I have my own chickens and did not want the flocks or roosters mingling. This went on for a couple of months where I was chastised for being un-neighborly for not allowing their chickens and their children to free range or play in my yard. I eventually called animal control. It worked. I have worked on developing better relations with them and have a better relationship with since they now respect my boundaries.