I have a 4 lbs, 11 month old yorkie girl. I heard that yorkies get a full coat by the time they're 1 year old. But mine's only has her coat half way, sorta looks like a puppy cut. She is shedding her baby hairs, but why is her coat still not grown? And yes, she is a very healthy puppy.
Don't worry mi Yorkie is 10 months and still has a medium size coat i quess it depends on each dog just like some people grow hair faster than other but it think is totally normal here is a picture of mine so you can take a look at him hes name is Tony.
http://s227.photobucket.com/albums/dd110/alejandre_07/?action=view¤t=letterHSBC114.jpg

That's not a true statement. It can take up to 2 full years for their adult coat to come in and to be full length. Good luck!
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I have 2 Yorkies.
Don't worry mi Yorkie is 10 months and still has a medium size coat i quess it depends on each dog just like some people grow hair faster than other but it think is totally normal here is a picture of mine so you can take a look at him hes name is Tony.
http://s227.photobucket.com/albums/dd110/alejandre_07/?action=view¤t=letterHSBC114.jpg
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I'm not sure how long their fur grow before their first year but mine is almost 11 months and I've taken her to the groomer serveral times to get trimmed. I do prefer hers medium length. I'm sure yours will eventually grow long.
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proud owner of a yorkiepoo and a yorkie