When Posy goes to stay at Pip's house they have lots of fun together before bedtime. But just as they switch out the light, disaster strikes: Posy realises that she has forgotten her favourite frog toy. Keen to help his distraught friend, Pip offers Posy a range of different toys to substitute for her frog, including his own favourite frog money box. But none of them will do: "That's the wrong frog!" Posy wails. It is only when Pip gives Posy his own, very favourite, pig toy that Posy is comforted and the friends can get a good night's sleep, at last.