Pitbull Question??????????????

As long as your sister socialized her dog and you socialized yours they should be okay. Dont have them meet in the house first because they could cause a territorial fight, go to a dog park and have play dates so they get used to each other before moving in. & depending on its size and your puppies size be careful pitbulls can play rough (though some play gentle just fine) and it may not mean to injure a small puppy but it can happen accidently so if there is a size difference just be aware of that. Make sure both dogs are spayed/neutered!