In 1998 Dr. Leon was approached by Lux Verbi to write a book on questions that children between the ages of about 4 to 10 ask about God and Jesus. He then approached churches and schools to ask children of these ages what questions they have about God and Jesus. Hereafter 25 questions about God and 25 questions about Jesus were selected. Of the questions were: Is God black, white or brown? Was Jesus in South Africa when He was on earth?
In 2005 this book was combined with those of two other authors in the Jy mag maar vra-series by Lux Verbi.BM in the omnibus: Jy mag maar vra omnibus.
In 2007 he was again approached by Lux Verbi.BM to write a book for adults on the developmental phases of the child: Die ontwikkelingsfases van jou kind. This is a concise book in simple language to better understand, handle and enjoy children in their respective developmental phases.