So many times she has wished she could swap places with Zoe. So many times she has sat by her daughter’s bed, at home or in the hospital, and silently intoned the same incantation: If I could give you my blood, I would. If I could swap your damaged cells for mine, I would do it in an instant.

Now, as she watches the life receding from her daughter’s body, one rasping breath at a time, she knows without a shadow of a doubt that if she were given the chance to swap places with Zoe, she would not hesitate.

If I could give you my life, I would.

Audrey does not know which is worse: watching her little girl writhe in pain and being unable to help or wishing that her suffering would soon be over in spite of what that means.

As Zoe breathes in and the air catches in her throat, her fingers squeeze hard around Audrey’s hand with a strength she did not know Zoe still possessed. For a brief, ephemeral moment, Audrey imagines that perhaps she is being granted the miracle Edward so fervently believes in. But when she looks at her daughter’s face—sees the pinching around her closed eyes, the tensing of the muscles across her forehead, the jaw slack and mouth open—she understands that this is not the beginnings of a miracle.

She holds her daughter’s hand as tightly as Zoe holds hers and waits for the convulsion to pass.

Clutching Zoe’s hand, Audrey remembers the first time she held Zoe in her arms. She remembers Zoe’s warm, sticky skin against hers, the flood of love so great it had temporarily washed away the unfinished pain that was yet to bring Jess into the world. During her pregnancy Audrey had worried that perhaps she would not experience the same intensity of feelings as she had with Lily, that perhaps there was a special bond reserved for firstborns, never to be replicated. But as soon as she had held Zoe against her chest—as soon as those tiny hands had clutched her little finger, as if holding on for dear life—she had understood that every new baby remade you as a mother.

Looking at Zoe now, it is impossible to comprehend that this small, frail ten-year-old is the same robust baby who had parted her newborn lips and cried out into the world, her voice loud and muscular, exuding a confidence that seemed to say: This is my life and I will make myself heard. It is impossible to think that Zoe and Jess—two halves of the same soul who have been inseparable for a decade—are soon to be cleaved apart.

She strokes the back of Zoe’s fingers, rubbing her thumb gently along skin so thin it is like touching bone.

She needs Zoe to know that she is there, that she would never leave her. Audrey understands that sitting here now, being with Zoe, is the most important thing she has ever done, the most important thing she will ever do. She could live to be a hundred and still there would be nothing more important than Zoe knowing that Audrey would never leave her side.