A child may substitute 'b' for 'd', write '3' backwards or turn a '5' in the opposite direction, and parents seeing this may wonder about dyslexia. But while it is important to address dyslexia issues from early, your child's problem may be a simple, normal case of letter reversal which is common in young children.
Dyslexia, meaning "difficulty with words", is a learning disability marked by difficulty in processing written language.
Dyslexics usually have problems with reading and spelling, regardless of what they're taught in the classroom. Additionally, they find it challenging to break words into syllables, 'sound out' words, and identify printed words.
Despite what many people believe, dyslexia isn't an indicator of low mental ability, because dyslexia occurs in many highly intelligent people.
In any case, there's no evidence that dyslexics literally "see" letters backward or in reverse order within words.
Letter reversals, on the other hand, are hardly distinctive to dyslexia and it is common for children age six and younger to do both backward writing and letter reversal.
But over time, the errors decrease in both dyslexic and non-dyslexic children, but for dyslexics it is on a much lower scale.
In addition, most research suggests that letter reversals are slightly more frequent, and in some studies no more frequent among dyslexic than non-dyslexic children. Letter reversals also account for only a small portion of the errors dyslexic children make, so they're certainly not a defining feature of the condition.