Liam found the "Chronicles of Narnia" set on the bookshelf and carried it around for a few days (along with "Matilda"). Nathan started telling him about "The Magician's Nephew" (first book in the series). And Liam kept asking for "Diggory" and always wanted to know what Diggory was up to.
He would pick up the book (he knew which one it was) and would start "reading", telling us what Diggory wanted and what he was doing. (I love his imagination!!)