IT CERTAINLY WASN’T intentional, in an era where the word of scientists seems to be continually disregarded, to write a book about the power of data, but here we are. Although we conceived of the idea before the pandemic fully hit, we wrote it during our respective states’ shelter-in-place orders, and this book will forever hold a sacred place in our hearts for the distraction and joy it brought us during such a dark time for the world. There was nothing about the process of writing this book that wasn’t escapist and rewarding, and for this reason (and about a million others) we are so incredibly privileged to do this.

We are also grateful for the group of spectacular people we not only get to work with but who’ve been our ride-or-die team this past year. We’ve taken turns propping each other up, which is the best possible scenario in a crappy year such as this. Before 2020, our love ran bone-deep, but the devotion now runs DNA-deep: Holly Root and Kristin Dwyer, we are your forever ride-or-die. Beyond what you’ve done for this book, what you give us daily as friends and colleagues is invaluable and we cherish both of you. Kate Dresser, your capability and warmth has kept our careers and spirits alive even when the world was (sometimes actually) on fire. Thank you for always being present—both emotionally and professionally—responsive, enthusiastic, and reassuring. We are the luckiest authors. Jen Bergstrom, thank you for always believing in us and, specifically, for believing in this novel. Your decision to put us in hardcover still makes us glow inside. We’ve been through every step of our career with you, and that means the world to us. Rachel Brenner, you are always a bright spot even on the crappiest days. Thank you for hustling, but also—and we mean this with our deepest sincerity and gravitas—thank you for always, always being willing to crack a dad joke.

To our entire Gallery team—Molly Gregory, Aimée Bell, Jen Long, Abby Zidle, Anne Jaconette, Anabel Jimenez, Sally Marvin, Lisa Litwak, John Vairo, the Gallery Sales team and foreign rights group: WE ADORE ALL OF YOU A WHOLE LOT.

The primary setting of the book, namely the apartment complex, is based on a real place! A place that is truly beloved to me (Lauren), in fact, and is owned by my much-adored aunt and uncle, Sharon and Clayton Haven, who retired, sold their house with a million stairs, and made the dream a reality, living at the apartment complex with my grown cousins and their families. We took some fictional license with the setting so that it worked for Jess and Juno, but in most ways our descriptions of the apartment complex are based on reality, and you can find more about this place in an LA Times story from February 15, 2019, entitled, “3 Generations in One Apartment Building? That Was the Grandparents’ Idea.” My aunt and uncle are two of the most precious people on this planet, and I am indebted to them not only for too many wild nights to count but for their enthusiasm, for their support, and for modeling a sense of adventure that has driven them for their entire lives. They find joy in everything; it’s so inspiring (example: Unc was seventy-five when he had the pleasure of seeing a reader ask us to sign her boobs, and I can still hear his laugh). You would have a hard time finding two more curious, thoughtful, and open souls in this world. S&C, I love you madly.