You can use reasonable force to stop any attack on your property. Usually, discharging a firearm in a residential neighborhood is a terrible idea, but you could do it to save a life. Non-lethal force would be much better. You can hire a contractor to fix/erect a new fence. You can also have a lawyer send a legal letter to these neighbors about the fence and their dogs' aggressive behavior. The lawyer can advise if a lawsuit would be a good idea. You should report the dogs' aggressive behavior as well as any barking to both Animal Control (which is the County) and the City as they will open files on the animals, and if they have a history, they can be confiscated. Report each time.
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