Move a slider and a train puffs into view making a train noise. Move that same slider back and a bus arrives instead, with a completely different noise. Two sounds per slider is the whole trick, and it doubles what a baby gets out of every single try, which is why this series holds a one year old far longer than an ordinary sound book does.

Ailie Busby fills the town with planes, trains, cars, motorbikes and buses, all of them driven by animals going about their day, drawn big and bright enough to be pointed at from across the room. The sliders work on a shove rather than on aim, so hands that cannot yet find a small button still get the payoff every time. That matters more than it sounds at this age: the reward has to be reliable or the book gets abandoned.

Eight thick board pages, two hundred millimeters square, and a book that gets played with on the floor before the wrapping paper is off.