As I lay in the dentist chair, listening to her tummy gurgling away like a grumpy anteater, it reminded me of our book of the week this week - which was instantly seized by Charlotte the moment she saw it during our recent #Libraryhaul (btw if you want to join in with that hashtag on Twitter, tweet us a photo of YOUR library haul, we always love to see what you've picked!)

We have loved David McKee's peerless "Not Now, Bernard" for what feels like forever. I loved David McKee's surreal and slightly irreverent but always entertaining "Mr Benn" as a kid, and we always love to see what he's going to come up with next. He might be getting on a bit now but there's seemingly no slowdown in his talent - as this book demonstrates perfectly.

Isabel is a fairly ordinary little girl - with a bit of an embarrassing problem. At inopportune moments, her tummy rumbles, grumbles, growls and groans. At school it becomes the class joke and always interrupts her teachers. At home, her mum wonders just what on earth is wrong with her - and dad tells her to eat her food more slowly, more quickly or take more exercise to see if it'll sort her digestion out.

Eventually the tummy rumbling gets so bad, the doctor is called in but he can find nothing wrong either. Poor Isabel becomes more and more miserable as her tummy just won't quit its noisy announcements.

On a class visit to the zoo however, Isabel saves the day. When a rather silly Zookeeper accidentally slips and opens the tiger cage during feeding time, Isabel's tummy roars just at the right moment, saving the entire class from doom.

There is a rather chortlesome pay-off at the end of the book - which I hope I haven't ruined. Suffice to say that some books are enjoyed purely because they mix a good dose of cheekiness with something that children Charlotte's age find endlessly amusing - bodily functions. You name it, they'll probably have a good guffaw about it, and this book makes book of the week purely for the fact that it made Charlotte roar with laughter nearly as loudly as Isabel's tummy roars!

Charlotte's best bit: Oh dear, well it has to be the bit at the end. Tsk, parenting fail that she finds things like that hilarious!

Daddy's Favourite bit: I'd give my eye teeth to have even a smidge as much talent as David McKee. A generation-spanning superstar of children's books and long may he continue!

Mischief, contrariness and a devilishly good tale here in a book where an innocent young boy is at the mercy of "The Opposite". Nate wakes up one morning to find a mysterious figure hanging from his ceiling. "The Opposite", as you'd expect, is a naughty character who gets Nate into trouble as he does the exact opposite of what's required in each situation. Sitting down for breakfast? Pouring out the milk carefully? Not if "The Opposite" has anything to do with it. Painting a lovely picture for teacher? "The Opposite" has other ideas. Soon, Nate finds that his day is disrupted and nothing seems to get rid of this pest - and nothing but trouble follows in its wake.

But can a smart little boy like Nate figure out how to outwit "The Opposite" ?

You will have to read the book to find out, of course! "The Opposite" reminded us a little bit of Levi Pinfold's brilliant "The Django" in story and theme, but we loved "The Opposite" (though perhaps some children might find elements of it a little scary and disturbing - The Opposite does a great line in Loki-style hissing! HSSSS!)

We couldn't get enough of the phrase "Then The Opposite happened" and I can tell this is going to end up becoming something of a family meme!

We like our books dark and thought provoking, and Nate proves that in some cases doing exactly the opposite of what's expected can actually work out for the best.

A fabulous original and darkly delicious story. "We really hated this book and will never read it again" (Then The Opposite Happened!)

Charlotte's best bit: Painting time with teacher. She laughed at that bit, but I don't think her teacher would approve!

Daddy's Favourite bit: Darkly funny, brilliant and original. "The Opposite" of atrocious!