Can pits have double dew claws?

My aunt recently dumped a 4 week old puppy on me. She said it was full blooded pit. Although i looked at her and she didn't look like it too me. I gave the puppy a bath to try and wash away all the bloody spots and fleas and dirt off of her. I realized she had a double dew claw on both back feet. She is a chocolate brindle color. Although she has a pits body she seems a little large for her age. Can anyone tell me any possible breed she may be or may be mixed with? Mastiff?