Prologue

The Christmas when I was eight, I received a magical snow globe. Within its smooth glass dome was a perfect miniature scene: a tiny Victorian house with glowing windows and a huge Christmas tree in the snow-covered front yard with lights that really lit up. A dog that looked just like our dachshund, Jack, jauntily wore a Santa hat.

But the special thing about that snow globe was that at the very center, two little girls bundled up in bright winter coats held hands, one blonde like me, the other dark haired like my twin sister, Grace.

I remember staring at it for hours, shaking it into a flurry of magical sparkles and peering in at that perfect little world that encapsulated for me all the magic of Christmas—the warmth of the glowing house, the miracle of snow, the happiness and comfort of family.

I clung hard to that magic because shortly afterward, my sister was diagnosed with leukemia, and the year that followed was a blur of doctor visits, cycles of chemo, and watching my mischievous, vivacious twin turn into a shadow of herself. All thenormalthat we knew tumbled down around us like boulders in a rockslide.

Cancer separated my childhood into a before and an after.Beforewas carefree happiness in the hugs of our mother, the winks and funny jokes told by our father, and the jostling and friendly torments from our two older brothers.

Grace got through her treatments. Later that year, on a snowy day just before Christmas, we were playing tag in the family room, scrambling around the furniture and giggling. I’d carelessly left the globe on the edge of the coffee table, blissfully unaware that it was perched on the brink of disaster. My sister had been feeling great that day, and I remember feeling so happy that she was done with her long road of chemo, that she was again my constant playmate and best friend.

It was the last time I’d felt that life was as it should be, everyone safe and tucked into place.

Right as she reached out to tag me, I twisted away, lost my balance and tumbled down, my arms splaying. The globe crashed to the floor, shattering into a million pieces as the water spilled, the magic swirling snow now just papery white flakes on the carpet.

“I did it,” I immediately confessed. “I did it,” I repeated, my voice a thin whisper. “I’m sorry, Mommy.”

“Shedidn’tdo it,” Gracie said, already sitting back on the couch, winded from our game. “I tagged her.Idid it.” She sounded a lot more convincing than I did. It had taken all of five seconds for her to decide on that lie, and she went with it.

My mother, hands on hips, looked the two of us over. “You girls certainly share everything, even the blame, don’t you?” She sat down on the couch and pulled me next to her, wrapping her arms around both of us.

“You said no running.” Grace’s lower lip quivered. She was still fragile. She wasn’t supposed to be roughhousing. That made me feel like I was doubly at fault.

My mother kissed my head. “I know how much you loved it, Mia. But it’s just a snow globe. Just a little thing to remind us of the fun Christmas we’re going to have.”

Our Christmas had been more than that, really, which I didn’t understand until much later. We roller-skated in the basement on new skates and on our frozen-over pond with ice skates. We made cookies and ate them with hot chocolate by the roaring fire Dad made in the fireplace. We played cards and games every night before bed. Even our big brothers seemed to pull fewer pranks than usual. Grace seemed strong and happy, and for the first time in so long, cancer had been abolished from our minds.

That was our last Christmas together as a whole and happy family.

My sister—my twin, my other half—lost her battle, and that broken globe became a reminder to me of just how fragile life is. How good fortune could turn on a dime. How happiness is a rare thing and not made to last. Somewhere along the line, I stopped expecting to find it.

Grace’s illness shaped me in more ways than I could count. She was the bold one who never hesitated to speak up. I was quiet and shy, always hesitant to speak my mind.

With her death, I’d lost my lightness. And my innocent acceptance of life as a beautiful, exciting journey. Because—why her?Whyhad God taken her and not me?

I became determined to make my life count for both of us. Iwouldbe cheery and kind. Iwouldbe smart and dutiful. And I vowed to never give my mom and dad a reason to cry again.

We had to pick up the pieces after Grace left us and somehow put ourselves together again. Which we did, but ever since then, it seemed I was always looking for the part of me that she took with her.

Chapter One

Twenty years later

Mia

“Here I come, Dr. D’Angelo!” Bianca Giarelli, one of my favorite patients, sped by in her wheelchair as I stood charting at the nurses’ station of the Children’s Wisconsin adolescent unit, where I was a third-year pediatric resident. The chair had an IV bag attached to a pole in the back, filled with an icky green liquid and swinging slightly as she breezed by. Bianca, age sixteen, had tied red and green streamers and a string of battery-powered LED lights to her pole, completing the Christmasy effect. I waved and gave her a thumbs-up as I talked into my phone, finishing a conversation with my mom as I worked.

“So, are you all packed?” my mom asked, sounding strong and well after the ordeal she’d just been through, which made my heart swell doubly with both happiness and relief.

After what had happened with my sister so long ago, you’d think my family would have gotten a pass on the C word. No such luck, but my mom’s breast cancer was caught early. She’dgotten through surgery and six difficult cycles of chemo. But now she certainlysoundedlike herself, and this nearly made me cry with joy. The doctors were extremely hopeful that she was going to be fine. Which was still terrifying, but we were dealing. And so, so grateful.

“Getting there,” I answered. It was Monday, and my four-day holiday break began after I was off the clock on Friday. “Can’t wait to come home for Christmas.” As my mom related what was new with my family, my eyes wandered over to my co-resident on the hematology-oncology service this month, Braxton Hughes.

Brax was actually the chief resident over the interns, the first-year residents, in our program. That meant he’d already completed his residency and had been hired on for a year where he had various duties like making the interns’ schedules, arranging and helping teach their educational sessions, and keeping an eye on their professional growth and mental health.

But this week, the week before Christmas, he was pinch-hitting on the ward for a resident who had to travel overseas to see his family for the holiday. At the moment, he was standing in the middle of the hallway consulting with Joe, one of our wonderful child life specialists.