I too have a Yorkie Poo! They can be very stubborn. Mine is 3 yrs old now but I was told to cage train her.

I took her out everytime she drank or ate anything in then at night before she went to bed.

At bedtime she was put in her cage with only room to sleep. In the morning we would go back to routine that she does her business outside.

She was very hard to train. When she did her business in the house, she was put in her cage until it was time to go outside again.

Once she realized that you're not allowed to do the business in the house, things went much better.

She still stayed in the cage at night for about 6 mos. When we trusted her again she was allowed to sleep with us. Any goofs and she was back in the cage.

Unfortunately consistency and routine to me is the key. Good luck
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