Sadly, a condition which can endure
In 1878 a German doctor, Adolph Kussmaul, introduced the notion of ‘word blindness’ (in German Wortblindheit) to describe a combination of reading problems and saying words or sounds in the wrong order which he had seen in several patients. But his name for this gave way to what is now known as ‘dyslexia’. Updating Kussmaul’s observation, it is now clear that there is a constellation of issues which commonly go together by what are known as ‘co-morbidities‘.
It is sometimes said that there are two sorts of dyslexia, being unable to see the shapes of the letters, or being unable to hear the differences between sounds. But this, like many other theories of dyslexia, does not explain why dyslexia and speech and language delay and disorders are so often co-morbid with one another.
In a corresponding way, it seems to me that the field suffers grievously from little engagement with either linguistics or with those directly affected.
Sadly, dyslexia is not just a developmental issue for a significant minority of children, but a condition which can endure, to a greater or lesser extent, throughout life.