What is wrong with my runt pitbull puppy since she isn't growing?

I have a 8 week old pitbull puppy. She is the runt of the litter but she is 3 times smaller than the rest of the puppies and she seems like she has stopped growing. What could possibly be wrong or what could be keeping her from growing?

Please take the puppy to the vet. Only they can give you an educated answer........There could be all kinds of things wrong. GO TO THE VET. You should have taken him there within 72 hrs of bringing her home for a wellness check.

Some people are just like this. They like to have the biggest and the strongest. some people will compare anything (my neighbor used to compare my sister and I constantly to her children, it drove my mom crazy) just to make themselves feel better. There are any number of reasons. It could be the different sexes (if that is the case) it could be genetics. There has to be a smallest in every litter.As long as your are taking care of your pup (and it sounds like you are, that is good food, its been to the vet) I wouldn't worry. Especially since your vet doesn't feel anything is wrong. My Lab was huge as a pup and ended up being rather small for a Lab. Dogs grow at different rates.ETA- the next time she says that jsut say something like "my vet and I feel she is a very healthy size. Growing too fast can be stressful on their joints"

Since the pup is only 8 weeks old, that means that you just got her. The breeder's contract requires you to have the pup seen within 48-72 hours after taking it home, so you can speak to your vet at that time. If the vet deems it to be a serious medical condition, the breeder's contract states that they'll either refund your purchase, or replace the pup with another one.