I tell this to every Yorkie owner who has potty training problems...patience and consistency really is the key to your success. Just remember to use positive reinforcement when your Yorkie does use the pad and eventually with the proper training you will start to see results. The guide in my signature has helped me and other Yorkie owners I know and saved us many headaches (thats why I help promote it!) But I do wish you luck with your training and I hope with some good training techniques that you begin to see results.
