Can you find out that you have dyslexia when you are almost in middle school?

I am writing a story and these kids are in the fifth grade and one of them finds out she has dyslexia. Is it possible that she couldn't find out until fifth grade. Maybe if she was home-schooled? Could you tell me a way that she could because I want to have a plot on the ninth book... which is when she finds out about it! THANKS IN ADVANCE!