In the first two Ruby books, Ruby’s slow and steady approach to life is shown in contrast to that of her impetuous siblings, Rufus, Rory, Rosie and Rebecca.
From a storytelling standpoint, it’s very useful for Ruby to have companions to talk to and play off against, but the large number of Ruby’s siblings created problems for both dialogue and illustration. If all four siblings were going to accompany Ruby on her adventures, I was obliged to give each of them something to say from time to time. And since all of them were ducklings, it was difficult to distinguish between them in the illustrations.
So for this third Ruby book I decided to give her a new companion. A single individual who, as well as providing the contrast previously provided by her four siblings, would have an appealing character of it’s own. I also wanted this new companion to be a different type of creature to Ruby, so that it would be easier to tell them apart.
It took me a while to settle on the companion's identity and I considered a frog and a kingfisher, before eventually deciding on Errol the gosling. Goslings look more ungainly than ducklings, but they are also larger and less delicate and this suited the character I had in mind.
The moral that some readers drew from the second Ruby book is that slow and steady wins the day. However, while Ruby’s measured approach is a virtue in many circumstances, there are times when acting fast is a virtue too. So, while Ruby’s approach pays off early on, in this story it is Errol’s impulsiveness that saves the day.
In the first two Ruby books, Ruby’s slow and steady approach to life is shown in contrast to that of her impetuous siblings, Rufus, Rory, Rosie and Rebecca. 
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