except their dogs beat the stuff out of his and its probably dying
and they killed his other dog
So what?
The neighbors didn't order their dogs to assault the OP's dog, the only thing that occurred here was nature doing what it's supposed to, dogs will be dogs as all carnivores will be carnivores, just because they're domesticated doesn't change such a fact.
You can't blame the neighbors simply because of nature, in a situation like this it's the OP/OP's fathers fault for letting a small dog sit around outside unsupervised when both the OP and his father knew that their neighbors have big dogs that are almost always outside, it's like you people forget that the food chain even exists