Google the condition in Yorkies but I seem to remember that during teething or something some of them can occasionally drop an ear or something but with good breeding of good, thin ear leather, strong ear muscles/ear cartilage, they usually right them again. Read about it in a very old Yorkshire Terrier breeder/owner/shower's book as I recall. Ask your breeder and your vet for any advice on whether or not you should add any nutrition/supplement or whatever to your pup's daily diet.
https://www.google.com/search?q=ear+...hrome&ie=UTF-8