I have never understood how people like that don't hear their dog bark.. I bet if it were YOUR dog barking they would hear it in a heartbeat.. Maybe they have the dog on the other side of their house from where they sleep? I think that phone calling of the dog barking is a great idea if talking to them don't help. Let THEM be kept awake and see what happens.
But I would try to talk to them as unemotional as possiable about it first and let them know that lack of sleep is a trigger for those awful migranes so it is not just a lack of sleep you are having to deal with. I would end with "and being the good neighbor you are, I know you will figure out how to solve this delima we find ourselves in...." (if he is otherwise a good neighbor)
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