The story was five years in the making, from the puppy coming home in a cat carrier, through all the antics and adventures; the training of pencils to draw puppies, and the coaxing of words and pictures to work together to build a story. 

A picture book has fewer words than other books, but that doesn't mean it takes any less time to write. The trick is to distil the  story down to a few words, and make the pictures work as hard as the words to tell the story.