I commented then, and have been thinking about it since, that the horror of this kind of betrayal is easier to understand if you have been a younger/st sibling, as Lewis was. I didn't co-create secondary worlds with my elder brother, but I certainly remember his outgrowing the kind of imaginative play that goes into them, and the bereft feeling that followed. When I read of Susan's denial, that was the string that vibrated. For those siblings who have lived together intensely in secondary worlds the abandonment must feel even keener. Did Warnie lose interest in Boxen before Jack was ready? Did Branwell go to the bad because Charlotte abandoned him in Angria?
I've been asking my students about it this week, and there was definitely more recognition of the pain of being left behind in this way amongst those who have experienced it - though that's hardly surprising. I do suspect, though, as I suggested the other day, that the whole psychodrama might have been been brought to wider attention earlier had Freud not been an eldest child. (Did that fact result in eldest child psychology being seen as normative? I don't know enough about the subject to say, but I suspect it may.) Afterwards, reading of Freud's daughter Anna's intense sibling rivalry with her elder sister Sophie and her subsequent specialization in child psychology, I wondered whether I might have better luck with her. Sure enough, her first paper, an account of her own analysis with her father, turns out to be entitled "Beating Fantasies and Daydreams" (1922).
I thought it an oddly Gradgrindian title, with perhaps more of a smack of the self-help book than I would have expected, but certainly intriguing given the subject of putting aside "childish" fantasies. Having read it I now know that it's actually about fantasies of beating. Cursed ambiguity of the English language! Nevertheless, although the Freuds (père et fille) see the fantasies as being about the father-daughter relationship rather than anything to do with siblings, I'm not so sure. And it's certainly intriguing that the fantasies themselves involve the elaboration of a mediaevalesque secondary world, which Anna goes on to turn into fiction. The final sentence is chilling, especially for fantasy authors:
By renouncing her private pleasure in favor of making an impression on others, the author has accomplished an important developmental step: the transformation of an autistic into a social activity. We could say: she has found the road that leads from her fantasy life back to reality.
Wo Anna war, soll Susan werden, indeed.