Everyone has a voice in their head – mine is just a little louder.

When I began The Divided Twin, I always knew the one person I was writing to—my oldest son, Austin Thomas.

“Austin, my Austin” is what my mom, your grandma, called you. Of all her grandchildren, you reminded her most of my father. You have his wonderfully round, Charlie Brown–shaped head and contagious smile, and when you laugh, it brightens the room. When you were little, you climbed—everything. You were fearless. If I turned around, you’d be on the backyard fence or on the highest rung of the jungle gym. What I didn’t realize was just how far you’d climb. From studying abroad to earning a double major in college, there is no height too high.

As the firstborn twin, if only by a minute, you have always taken charge and worn the mantle of responsibility for your brothers and sister proudly. You are the protector, the overachiever, and one who leads with his heart. You fearlessly approach life with drive, compassion, and strength with an unending spirit that never gives up.

Austin, you are my hero.

And I couldn’t have written this book without you. When I was diagnosed with breast cancer, you were the child who tried to make my life easier. My sweet son, from the depths of my heart—thank you.

Parts of the letter you wrote me when I was diagnosed are included in this book. How could I ever write anything better or more heartfelt?

You would make any parent proud. I’m the lucky one who gets that honor. And being your mom is the greatest gift I’ve ever been given.

Keep climbing.

Austin, my Austin, I will love you forever and ever.

—Ma