My son liked the story (from age 2.5yo when I bought it) - we kept it by the potty and he kept asking to read it. Quite possibly helped him recognise the feelings of needing to go (now 3y9m and still occasionally talks about the 'poke in tummy with stick' feeling) and realise what it's all about, though didn't obviously 'do the trick' and help him to easily use the potty/toilet. There are some good bits to the book, like the illustrations showing how poo is the waste left over from food, but I didn't like the American language (though easily substituted for British terms when reading through) nor some of the illustrations (sepia shades in the middle, when relating Bill the Coyote's story of 'trash' in his house.