The Chronicles of Narnia (although we do not learn their surname until "The Voyage of the Dawn Treader"), and eventually become Kings and Queens of Narnia reigning as a tetrarchy. Although introduced in the series as children, the siblings grow up into adults while reigning in Narnia. They go back to being children once they get back to their own world, but feature as adults in "The Horse and His Boy" during their Narnian reign. All four appear in "The Lion, the Witch, and the Wardrobe" and "Prince Caspian"; in the latter, however, Aslan tells Peter and Susan that they will not return, as
The Chronicles of Narnia book: Lewis's interest in the literary symbolism of medieval and Renaissance astrology is more overtly referenced in other works such as his study of medieval cosmology "The Discarded Image", and in his early poetry as well as in "Space Trilogy". Narnia scholar Paul F. Ford finds Ward's assertion that Lewis intended "The Chronicles" to be an embodiment of medieval astrology implausible, though Ford addresses an earlier (2003) version of Ward's thesis (also called "Planet Narnia", published in the "Times Literary Supplement"). Ford argues that Lewis did not start with a coherent plan for the books, but Ward's book answers this