[lish888]

My sister got a Boston Terrier dog. Few weeks later Bella gave birth to one puppy. The puppy is now 5 weeks old and it is apparent that he is not full Boston Terrier. His nose is longer, he is brindle and he is huge! Any ideas on what his dad might have been?

[cigwyllt]

There is no way to tell. You'll have to wait until he is at least 8 months or so before taking any sort of guess about his breed. Puppies like human babies change so much as they mature it can be impossible to match the new pup to the adult.