Prologue
RACHEL
Four years ago
They never tell you how much it sucks to be the exception to a rule.
Math books worship probability. Medical journals obsess over averages. Case studies, percentages, median outcomes—etcetera, etcetera. There’s always a neat little sentence tucked at the bottom:Outliers do not significantly skew the data.As if that’s supposed to be comforting. As if being statistically insignificant makes the experience hurt less.
They outline the rule. They bold it. They underline it. They build the world around it.
And if you fall outside the margins? You’re a footnote.
I never thought much about outliers before. I was content to live inside the bell curve, tucked safely beneath whatever promise the rule provided.
That is, until today.
The Rule: the only person who stays with you for your entire life is your sibling.
They are there before memory, before language, before the world teaches you how to be afraid. They arrive beside you at the beginning and grow up in the same house. You learn the same lessons passed down from your parents, and absorb the same love or lack there of.
At some point, they become your partner in crime. And during other times of your life, your tattletale. They can be your safe haven, a sounding board at two in the morning. The keeper of your worst secrets and your best ideas.
And other times?
They’re your argument. They can be the hand that pulls you out of trouble and the reason you’re in it to begin with.
However, for me, Josh was my first and strongest best friend. He knew who I was before I learned how to pretend to be someone else. Before I polished myself for the outside world.
You lose people as you age. It is the inevitable reminder that this world is finite. The quiet bargain of being alive. Your grandparents fade first. Then, if you are lucky enough to watch them wrinkle and silver, your parents follow one by one, until their voices exist only in your head. Friends drift in and out of your life with time and distance. Lovers step into your life believing they’ll stay, and sometimes they do—for a while. Even your children, if you have them, meet you long after the beginning, when you’re already shaped by years of living without them.
But a sibling is meant to be the constant. That is the rule.
From beginning to end.
And yet—
I must be the exception.
The statistical anomaly.
The outlier that doesn’t skew the data.
Chapter One
RACHEL
Now
“Ican’t do this,” I whisper, leaning toward Slone, my fingers tightening around the stem of my champagne glass. My palm is slick with nerves, and I swear my voice is trembling.
“Yes, you can.” Slone bumps her shoulder against mine, her lip gloss catching the reception lights as she smirks. “You’ve practiced this a hundred times. You could recite it in your sleep.”
“Practicing in my bathroom mirror doesn’t count.” I drag in a breath, trying not to look at the crowd of laughing, glittering faces. The hum of conversation and clinking glasses feels deafening. “This is different. Everyone is watching me.”
My gaze flicks across the room, and all I see are polished smiles and expectant eyes. A stupid thought hits me:What if I mess this entire thing up for Margo?
I force a smile, pretending it’s all fine.