Why does your Yorkshire terrier at 6 months old weigh 12 pounds and his sisters are smaller?

Your Yorkshire terrier may weigh 12 pounds at 6 months old due to a combination of genetics, diet, and overall health. Variations in size among siblings can occur because of differences in their parents' genetics and environmental factors. Additionally, if your puppy has been consuming more food or a richer diet compared to his sisters, this could contribute to his larger size. It’s important to monitor his growth to ensure he remains healthy and within a suitable weight range for the breed.