Although it was considered simplistic and easy by many, the illustrated children's book faces at least two challenges that make it interesting even for demanding readers: On the one hand, the fact that it addresses a particularly heterogeneous and expanded audience, since its young readers, not yet knowing how to read, require the assistance of adult co-readers. On the other hand, two codes construct a story that is neither the one narrated by the words nor the one shown by the pictures, but a third one that emerges from the collaboration of the two. Servant of two masters, the illustrated children's book manages to speak to the child while simultaneously addressing the adult, and at the same time, it is read as a verbal text and observed as a series of images. In this book, which is aimed at educators, parents, students, and all those interested in books and children, the illustrated book is studied as a genre that not only challenges but also deserves the love of both young and old.