In tribute to his late wife, the author wrote: 'On a frosty morning I watched gold finches feeding from the crisp seed head on a teasel in our garden. It had grown in front of a garden lamp modelled on the traditional street light described in C.S. Lewis 'The Lion, The Witch and the Wardrobe' and 'The Magician's Nephew'. It was our last Christmas present to each other several years previously. Just like the teasel, one could say that she had also grown up in the illumination of the Narnian light. Looking at the teasel it struck me that the good that one does in life, whether overtly or quietly in the background, lives on to nourish others after death.'