[topknot]

If it is an outcross - the breeder will not know. You need to go farther than just the parents to guess weight better - need to know grandparents as well. Weight can never be guaranteed, only a good guess for a breeder that knows her lines and how her puppies developed. That takes years and for the breeder to keep in touch with all the buyers s/he sold their pups too. The best guess, rule of thumb, is to double the weight at 12 weeks, but no guarantee. Yorkies are ones that can grow at different rates and in which depends in the lines (combination of ancestors) - some grow very fast at the beginning and then stop and some grow very little over the 2 years till they reach their adult weight. I have seen this with mine. So you just cannot be sure. I do look at the holes of the nose - if they are very small - like pin holes - they tend to be on the smaller size. Also look at the paws and bones. Ones with bigger bones and paws tend to be on the larger size. But you also have food and nutrient that can also effect them.

Remember -adult weight of a puppy cannot be determined by only the parents!

And adult weights of the ancestors are not in their papers or pedigree. Papers are completed when the dog is a puppy, so they are not even adults yet.