We visited my sister in law this evening and my son enjoyed playing with her dog. When my son chose to lay down in the living room carpet, he wondered why the dog didn't follow him. We're having fun watching him so puzzled on why the dog stopped following him and just stared at him. He's too young to understand that the dog is not allowed to step-in the carpet and it's possible because of the dog training device. But, my sister in law mentioned that he bought also a collar tracking device too because whenever they go hiking and do other outdoor activities, they bring with them Max, (dog's name) so a tracking device is a must. She loves her dog very much but complaining about the saft batteries of the device. She needs to replace it and the seller of the device charged too much so she want to scout for other sources/sellers.