Title: Diary of a wombat. Author: Jackie French; illustrated by Bruce Whatley.
It's a picture book; but, as the guy at the checkout of Waterstone's said - adults love it - he doesn't know, what kids make of it. The illustrations are quite clear and always get it just right, be it the expressions of the typically Australian couple and two kids being covered with dust at the barbie (wombat is taking a dustbath), or wombat's fight with "flat, hairy creature" (doormat). Sat in the bookshop and couldn't stop laughing while I was reading it, I had to buy it... (One of their half-price offers at the moment, so it didn't hurt too much!)
An example of the style of the diary:
Monday
Morning: Slept.
Afternoon: Slept.
Evening: Ate grass.
Scratched.
Night: Ate grass.
Slept.
Oh, and the pets this book deals with are the humans - wombat tries to train them up properly, and more or less succeeds.
I know that this book is going to stay in my possession - no way am I giving that away!
(Wombat - do you recognise yourself in that diary???)

Ina