As a child I had access to lots of books and was actively encouraged to read. Which I did. A lot.

At the age of 7 or 8 I attempted to read The Decameron and The Canterbury Tales. I tried and tried but couldn't make sense of the archaic language and turns of phrase. Using the dictionary only helped a little.

Over the span of the next few years I came back to those books, and each time I was able to read a little bit more, understand a little bit more. By the time I got to High School Shakespeare and Chaucer were not challenging for me as I was already familiar with these literary styles and the authors' quirks.

Reading, and reading often, helped me to build grey matter muscle memory and things that were once "impossible" or "too hard" became not only possible but educational and even enlightening. Please, if you have young children read to them and encourage them to read as wide a variety of books as possible. Their life will be enriched forever if you make this investment of effort now.