Well, I don't think the answer has changed much since last year when you asked about Todd's size.
http://www.yorkietalk.com/forums/cal...ml#post3841445
There really is NO way to know for certain how big or small a puppy will mature to. You'll find predictors but that's all they are. To me, it sounds like this breeder may not have been looking out for this pup since a good breeder will usually keep a puppy until 12 weeks (for health & learning of the pup).
I want to encourage you to check out the YT library here on this forum. You'll find it very helpful. It's one of many Forums (shown when you click on the word Forum at the top of the page, under Yodi the Yorkie's picture.)
Good luck with your new pup.