My Jeter was estimated to be about 4 to 4 1/2 pounds, that was going with what past litter's of his parents weight turned out. His dad is 4 pounds and his mom is 5 pounds.Jeter was from a litter of 4 and was the 2nd smallest of the litter. I brought him home at 10 weeks old and he was 1 pound 2 ounces, he gained weight very slowly so I would take him in for weekly weight checks at his vet's office, they are just a block from my house, witch came in handy for me cause I worry all the time
When we got our other 2 Yorkies when Jeter was 10 months old, they quickly out weighed him after a few weeks
He is 14 months now and he is only 2 pounds 8 ounces
He doesn't realise that he is so small! He puts the other 2 of our Yorkies in place when they play lol! Our Axl is almost 8 pounds and Yumi Yasha is almost 4 and they are now almost 7 months old. So their is a big difference in size with them. He is currently the smallest adult Yorkie our vet treats right now, and he is extra cautious with giving him his vaccinations and meds. My vet does not think a 2 1/2 pound dog needs the same amount of meds as a 20 pound dog, thank goodness!