How old is Bruce supposed to be in show? We know Thomas wrote the letter before his death when Bruce was 12. At the minute I'm guessing Bruce's age is either 12 or 13 since the letter would be more poignant if it was the last thing Thomas wrote before his murder. That would make Bruce 12 at the time of the Wayne murders and since season 2 is only set a month after season 1, depending on Bruce's birthday, that would make Bruce still 12 or at the most just turned 13. However, I would've thought if Bruce did have a birthday, the show would've shown us that since it would've been his first birthday without his parents and the perfect opportunity for an emotional moment between Bruce and Alfred. The letter is only "evidence" of Bruce's age insofar that it tells us that Bruce is at least that age at the beginning of the series but it doesn't tell us how long before the Wayne murders it was written. Is there any other evidence in season 1 or 2 that could indicate Bruce's age?