Winnie-the-Pooh and the Day of Very Important Letters by A. A. Milne
When Pooh visits Piglet with a Very Important Letter one morning, a day of mystery begins for all the animals of the Hundred Acre Wood. Who is the mysterious 'X' signing their letters, and why are they all being gathered together? Consisting of a lovely story, six Very Important Letters, a map and a party hat too, all is revealed in a joyful ending in this wonderful book.