Win a copy of "My Sister Rosa"

We have the new book from YA author Justine Larbalastier up for grabs this week. Called My Sister Rosa, it has already recieved great acclaim from reviewers.
"What if the most terrifying person you'd ever met was your ten-year old sister? A spine-chilling psychological thriller from one of Australia's finest YA authors.
'I promise,' said Rosa. 'I won't kill and I won't make anyone else kill.'
I can't see the loophole. Since the guinea pig there's been nothing. Months now without Rosa killing as much as a mosquito. As far as I know.
Che Taylor has four items on his list: 1. He wants to spar, not just train in the boxing gym. 2. He wants a girlfriend. 3. He wants to go home. 4. He wants to keep Rosa under control.
Che's little sister Rosa is smart, talented, pretty, and so good at deception that Che's convinced she must be a psychopath. She hasn't hurt anyone yet, but he's certain it's just a matter of time. And when their parents move them to New York City, Che longs to return to Sydney and his three best friends. But his first duty is to his sister Rosa, who is playing increasingly complex and disturbing games. Can he protect Rosa from the world - and the world from Rosa?"
To be in to win via email, send it through to info@booksellers.co.nz with the subject line 'Rosa', telling us who the most terrifying member of your family is and why, and including your physical address. Competition closes at 12 noon on Thursday, 7 April. The winner of the two copies of Quicksand, by Henning Mankell, were Michelle Dyer and Anna Tims.
Please note that we only accept one entry from each person - any double-ups will have their extra entries removed from the draw.