My Yorkie isn't even let outside by herself.
I'm sure she would be happier spending her days outside but it isn't safe.
If the pen is uncovered, you have the threat of other animals attacking.
Even if it is covered, some Yorkies don't do well when it gets too hot or too cold. I would not want to take the chance of heat stroke or hypothermia. Yorkies are inside dogs. They also have a very high theft rate. It just is not safe to leave them outside alone ever. You obviously want what's best, so I say listen to your wife.
