We've discovered celebrities we never knew were twins, colleagues with twins have brought themselves forward and have also heard some amazing stories about the bond between twins and their special secrets.
Do you know any twins? Are you a twin yourself? And do you have a story you'd like to share? Leave a comment in the box below and tweet us @piatkusbooks #thetwinsbook and we'll pick one lucky winner to receive a copy of the book for free.
The competition opens today and closes on Sunday 15th September – may the best story win!
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