Tara had 5 pups this past fall and all were about the same size at birth, but by 2 weeks old one was HUGE, and she's turned out to be easily twice the size of t he others now that they're 5 months old. If you don't have one already, run out to Target and get a scale (a meat scale with a nice sized, flat measuring bowl is what I use, only about 15 bucks). Just weigh the pups daily to make sure they aren't losing weight. If the pup is losing, or looks smaller than it did earlier you need to take him to the vet asap. He's probably having some type of problem with feeding. If he's making gains, I wouldn't be worried. Our little Leia was super teeny all through her "infancy" but she gained little by little and is a happy, healthy pup. Good luck, hope all goes well!
