"The girl in the mirror" by Rose Carlyle

An audio book.

Iris (it's her PoV throughout, she's 23 years old) and Summer are twins, identical, though Iris has internal organs the opposite side to usual. She's a lawyer who's recently broken up with her boyfriend. Their mother Annabeth, their father's other wives and offspring are still around. Their brother Ben is gay. When her father died (she was 14), he arranged $100m to go to the first grandchild born within marriage. Summer (ex-nurse) is married to Adam whose first wife died (Summer was her nurse). Adam's son Tarquin is more than 2 years old and mute.

Summer's family is cruising in their yacht Bathsheba when Tarquin falls ill. Iris flies over to help Summer sail the yacht away. Summer's pregnant. She goes overboard. Iris wonders how to break the news on her arrival. Misunderstandings and the situation tempt her to say that she's Summer. She has trouble maintaining the pretence - she's not pregnant (she tells Adam's cousin she miscarried on the boat), she knows nothing about childcare, Adam's into BDSM role-play, and any medical examination will reveal that her heart's strangely located.

She gets herself pregnant but she's over a month behind what people think she is. Summer was more popular than her - her mother says she considered Iris a lost soul and never understand her. Virginia, a half-sister, has been encouraged by her mother to get pregnant. She's sent to New Zealand to married a cousin when 16 and her mother gets her to have sex 3 times a day. Her cousin isn't happy about it, nor is Victoria. Iris plays the piano badly (like Summer) then improves. "The piano seems to have the soul of Bathsheba, the soul of the ocean."

Tarquin's first sentence is "You're not my mother".

Iris's waters break. She has a daughter. Ben turns up after 7 months of non-contact (he hadn't come over after Iris's death). He knows straight away that she's Iris (though Iris's mother had been living with Iris and Adam for months without realising) and she deals with the situation as if she expected it.

Summer appears. Iris copes well with the surprise. Summer says she's wombless and it's all been a plot to get a child (which I hadn't anticipated). While they're fighting Ben shoots Summer from a distance then returns to New York while Iris returns to attend the delayed ceremony for Iris. But actually Ben shot Iris.

When one of the twins is shot dead I presume the author expects readers to be unsure who the victim is. Before then I think the twists work, though the behaviour/reactions of characters are often hard to believe. The $100m reward is so high that extreme reactions are likely, and with twins around, there are few new plots left. I didn't believe that Iris would adopt Summer's identity - too easily discoverable by mother or doctors. Even if Ben disliked Summer, his behaviour is strange.

I think the writing's ok. "Another wall of pain slams into my body" doesn't work for me.

Other reviews

• Toni V. Sweeney (Summer is the dominant twin, but she’s not as perfect as everyone has always thought. Her secret has nothing to do with the order of birth. Their father’s will is only the catalyst bringing her true nature into the open. In the beginning, Iris strives merely to keep her sister’s memory alive, but as she becomes deeper involved in her deception, her personality gradually dissolves into Summer’s, into the time when she and her sister were one.)