I had a similar issue arise with another yorkie that I did not adopt (there were congenital issues.) The vet said that by the looks of the teeth (all were baby teeth) the puppy was 2 months younger than stated by the person I got him from.
After consulting with other vets and through online resources, I learned that the puppy actually may NOT have been younger after all.
Yorkies teeth may develop later than other breeds. It's apparently NOT uncommon for yorkies to have baby teeth beyond the normal time frame. I also learned that many vets don't appreciate the unique development and maturity patterns of the yorkie breed.
That's not to suggest that an unscrupulous 'breeder' wouldn't alter records to mislead a buyer. I'm only saying that in some Yorkies, the teeth may develop later.
Good luck.
Tracey |