I have never seen a mute Yorkie or heard one, wait, it they are mute I couldn't hear her anyway. I've got a beautiful little girl Morkie that many days would like to trade for a mute puppy. Belle is very vocal to say the least! She has a different bark for almost any occasion, and now she has developed what we call a trill. She sounds like a loud bird, it's kind of cute except when she does it cause she's not getting her way, then it sound pretty pathetic. I bet your baby will be just fine, in a few months you will be missing the quiet. If your vet says it's catching let me know, maybe Belle will come and visit