I'm not completely agreeing with
@Mariella posey here.
I'm really sorry about your friend Mariella, death threats are awful and absolutely stupidly unnecessary and scary, but I choose to trust OP here when she says that dog is beaten and neglected, because she is the one person here who would know for sure what is going on..
And OP says they cant do anything, so why are you telling them to? OP loves the dog so I really think they would if they could.
I'm really glad to hear you just give your dogs a 'quick smack' with a stick, and hate doing so, but that does not mean that is what OP's neighbours are doing, why would that follow? Maybe we are being melodramatic here, but I think we should listen to OP and we are all concerned for the dog and her puppies (And now for OP!)