You said this is your 7th dog, but is it your 1st yorkie? My 1st dog was a lab mutt from the humane society & even though he was only 9 weeks old when I got him, he instinctively knew to go outside to potty after day 1. Everything I read prior to getting my yorkie said how difficult they can were potty train, but I just really had no concept until I experienced it for myself. All I can say is consistency is the key. The fact he knows the words is a great start, but they are stubborn little creatures and knowing what to do and actually doing it are 2 different things (kinda like teenagers...). Good luck. Stay with it and you will be rewarded with a well trained dog. (And then there is always laminate flooring...
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