Can you tell me if the runt of the litter has more problems? I recently found a chihuahua puppy for sale. Went I went to see it the person had two puppies left. Both 8 weeks old. One was the runt of the litter and was about half the size of the other. The other one has since been sold but I think the tiny one is still available. I've never owned a dog before though and am not sure if I should worry about anything with the runt. Any thoughts or advice? Note: She looked very healthy and was very playful - was just very tiny.