It's set in a parallel universe where birds fly backwards, people shrink when they get bored and on Thursdays the fish go shopping (see below).

I've drawn it out with my appalling handwriting and have illustrated it (badly). I got the idea for the design of the book as a great aunt of mine who lived in England wrote a book for me when I was a child, with this layout. (However there were a couple of reasonably major differences between her and I, she was an artist and a published author so her drawings were a lot less amateuresque and her story far more skillfully crafted.)
Anyway I'm just pleased I've finally finished. All forty-three pages of it (it even comes with it's own bookmark due to those forty-three pages making it a little long to read in one hit if you're small).
But what makes the whole thing worthwhile is that my godson got it for his birthday this month, and he loves it.
As I say, I started it when he was born.
He's just turned seven.