My new puppy Mckenzie is 12 weeks old and at her last visit w/the vet the day after I got her, she was nearly 2 lbs, although the breeder said she was 1.5. The vet did say she had a full tummy though, so I'm guessing 1.8 lbs is her 3 month weight. I hope she'll be a 4 lb baby. Her breeder mom said she would be shocked if she made it anywhere close to 5.. she predicts 3 1/2 but said you can never be sure.