20-YEAR-OLD Siri was born with a rare brittle bone disease called hypophosphatasia (HPP) - she just didn't know it until three years ago. Having broken numerous bones and teeth "with ease" throughout the course of her life, Siri and her mom Katherine suspected for a long time that there was an underlying condition at play. Siri told Truly how she "broke three ribs getting out of bed" and "shattered a tooth just eating a sandwich" and with no official diagnosis until she was 17 years old, damage had already been done. A particularly complex break of her elbow when she was just five years old was repaired by doctors at the time - or so Siri thought. Unfortunately, her bones did not heal correctly and she was left with a trapped nerve in her arm - something she recently underwent surgery for, 15 years on from the original injury.