LOL!
Thats funny about her hunting instinct. I have a Yorkie/Bichon Frise mix, Abbie (Yorkiechon)... anyhow, she is all Yorkie in my book, she looks like yours. You should hear how she BARKS and SNORTS and digs and kicks her front feet in the lawn when she sees a Possum up on the fence. Scares me to death, because the Possums I've seen here are 3 times her size, bigger than cats! So I run out to get her but it's impossible to catch her. So I just make noise to scare the possum away back over the fence into the neighbors yard. So far I've been lucky that neither of my little rascals have gotten close enough to take on any of these wild animals (I have a Shih Tzu also that wants to catch them also!).
I've looked at my Abbie's teeth... they are HUGE for such a little dog!!! I guess thats why, they are hunters!
Welcome!!