I'm going to be blunt but I'm sorry. The dog has next to no human companionship, is tied up inside the house, goes out for a walk once a day (does the dog get let out to potty at all??) and your mother hits the dog. I disagree with just about all the advice given, not that it's not good advice, it is but I'm sorry, your mother does not deserve any dog and this dog needs to be found a new home. No amount of training is going to help, it's the human who needs the training first and that's just not going to happen. Again, I'm sorry but geesh, this is a living breathing being. Do the kind thing, do a google search for a rescue and take the dog to the rescue.