Quick: bring something to read to him on the train! This last-minute thought, just before setting the burglar alarm, sends me rushing to the pair of small bookshelves outside the bathroom which contain the old Ladybird books. Which of them shall we take? Rapunzel, Rumpelstiltskin, Florence Nightingale, The Princess and the Pea, The Fireman. They’ll do. They fit into the handbag, and I set out knowing that, even if we run out of water and KitKats, and there’s no refreshment trolley, we’ll have enough mental nourishment to keep us going through whatever South West Trains might inflict on us.