User blog comment:NattieFinn/Could you ever have a Greek in a Roman camp?/@comment-4528975-20111105205430

They would notice if a Greek was in a Roman camp. Octavian knew that Percy was Greek. The wolves at the Wolf House knew that Percy was Greek. Juno probably told Lupa about her plan to unite the Greeks and the Romans. Greeks are hard wired for Ancient Greek. It's probably the same for Romans.