My sister Rosa by Justine Larbalestier

Allen and Unwin, 2016. ISBN 9781760112226
(Age: secondary to adult) Highly recommended. Crime, Thriller, Siblings, Mental health, Psychopathic behaviour. Che has always looked after his much younger sister, Rosa. Their parents are focused on their business, so the two children are taken along with them, this time to live in New York working with their father's long time friend. His children, twins of Rosa's age and a girl about Che's age, are expected to get along, but Che becomes aware that Rosa is pushing the once close twins apart, and manipulating one to be her close friend.
Che is worried. Rosa has shown these traits before, and specialists have diagnosed her as lacking in empathy, a psychopath.
Che has four things on his to do list. One is to look after Rosa, a role given him by the parents when she was born. Next is to find a girlfriend, then to spar and finally to go home to Australia.
Each of the four sections in this thrilling book tackles each of Che's aims in turn.
In looking after Rosa he talks with her often, teaching her how to be more interested, how to talk to people, how to use and decode facial expressions. In doing so, he inadvertently gives her more tools with which to to manipulate people more easily.
Rosa's character is amazing. She is able to wrap most people around her fingers, using her Shirley Temple looks to contrive and deceive.
Che reveals the extent of her ability when she manipulated one girl into killing her pet guinea pig, and so the reader is warned about what else she might be able to do. When Rosa's new friend eats peanut butter even though she has an allergy, Che realises that he must watch Rosa far more carefully as he is convinced that she is behind the event. And so a cat and mouse game evolves.
Meanwhile Che loves to box and finds a girlfriend in the gym he attends. She is bound by her religion, one of her mothers is a minister, and the discussions they have are fascinating, opening up a field not generally discussed in young adult literature. Che has promised that he will not spar but one night does so, only to find that Rosa has brought his parents to the gym. He has told her not to lie, and so she 'innocently' tells her parents of his intentions. The fourth aim on his list becomes less a focus as his relationship with Sid develops, and he becomes more used to New York.
But it is the power play between Rosa and Che that piques the interest of the reader. Tension mounts as Rosa becomes more adept at twisting words, as she and her new friend use a secret language to baffle and exclude, as Che's parents reveal some of what they know.
The climax of the book is shocking, the girl's powers mind boggling, her manipulation of events almost landing Che in jail. The subsequent medical examinations of all three children reveal yet another layer of intrigue and readers will not be able to put this one down. Packed with a huge range of diverse and multi layered characters, many hiding something they know, the atmosphere of the gym, the closeness of the two families, the pressure of Sid's religion, all contrive to make the reader feel claustrophobic, entrapped in this little world, despite being in New York with all it has to offer. Rosa seems to be pulling the strings making everyone dance for her own entertainment.
Larbalestier always enthralls: her original stories weave their way into the readers' minds, grappling with bigger issues that continue to fester long after the last page is read.
Fran Knight