In addition to my last post, I agree with others that it's obvious you care about the dog and really do want to help it.  However, it also seems you're short on cash, which means you probably can't afford to be hiring a dog behaviourist or trainer.  That's why I suggest re-homing.  Your sister could take the dog, but sounds like she ALREADY re-homed it without actually calling it that.  I think you have every right to re-home this poor little pup again, hopefully to a family or person who has the time and resources to help it find a happy and balanced life.     
				__________________  David & Denise   ... proud parents of Ozzy        |