As far as I know, all Yorkie's hair WILL grow. The length and time depend on the dog. To help it grow faster, you can feed them Omega-3 fish oil vitamins (the ones for dogs of course). Also if you give them an egg yolk once in a while, it will help keep the coat soft and shiny! I would start off giving them an egg yolk once every two weeks, or every month. Then you can maybe give it to them once a week. MAKE SURE NOT TO GIVE THEM TOO MANY!!. A good daily brushing with detangling spray will also help give them a shiny soft coat, and help their coat grow! Your dog is very cute and these tricks should help her coat get longer!