Although the previous post is very entertaining and I loved it, we understand the OP is not terribly bright, so let me break it down.
You are not responsible for your neighbors dog. Puppies born out of wedlock are not your responsibility. Your neighbor can go jump... apparently someone needs a higher fence.
There is absolutely NO legal cause of action available to your neighbor to do anything legally.
If you want to help out as a good neighbor to maintain neighborly relations, fine. If you are threatened, you can just laugh and ROFL.

