When the immune system attacks itself.
Her sexual behavior, smoking, and drinking are controllable risk factors.
She cannot control her age nor can she change the heredity she has.
By stimulation of the organ through exercise.
I don't believe dyslexia is a born disorder, and can be developed at any stage of life, given the circumstances leading to the development. It doesn't occur out of the blue, there is always a reason for the development of a learning disorder. I would not jump to the conclusion that you have dyslexia, though. It is simply a possibility. Other reasons your reading and writing could be affected includes lack of sleep, hormone rampages, environmental changes, etc. etc.