When 11-year-old Dariush Namin returned home from school one afternoon last January and told his dad that the back of his leg was sore, his father Francis didn't think much of it. Perhaps it was just a bruise his son had gotten while playing at school.
A few days later when Dariush mentioned his back and wrist hurt as well, so much that he was unable to clutch items, Francis realized something was seriously wrong.