[QUOTE=Piper]
 
 
I posted here recently about purchasing a second puppy.  My little boy, Angus (4 lb.), was missing his buddies.  There were two Yorkies, Pepy and Pica, who lived next door, and he used to play with them all of the time.  After much thought and research on the matter (realizing he needed the company, and we love Yorkie's so . . . it wasn't a problem), we decided to look for a little girl.  I purchased one who was 6 weeks old.  We have had her be 4 or 5 pounds full grown.   
First of all a Yorkie at 6 weeks should still be with her Mother that is way to early to let go.. 
2nd  no matter  what she weighs now, you can not  determine her adullt weight at tthis point.  Every good  breeder will tell you  that. 
Last, was this puppy  checked by her vet, did  you get her vet papers? 
I would  be willing  to bet the  breeder will   not take her back and  refund your money.  Keep us posted.