Cake:  Garden cake with fence, carrots, peter rabbit figurines shaped into the open pages of a book.  Other snacks included carrots, blackberries, and other vegetables from the garden.  Games:  give each child (with parent) a clue and the search in the garden (back yard) for the item. I had "peter rabbit 'treats hidden in goodie bags which they were looking for. For example: a clue could refer to the watering can where peter rabbit hid and in the back yard I placed a watering can and inside was the "treat". Entertainment: I had a Puppeteer do a version of "peter rabbit" as a puppet show--basically reading the book. Goody bag: I gave each child a Peter Rabbit coloring book (1.99). Other Fun: Have a child play Mr. McGregor and chase the other children. Taking turns as he "catches" them.  This was a great FOUR year old birthday party for boys and girls and my son still talks about playing peter rabbit and mr. mcgregor chase in the backyard.