Whatever I was supposed to navigate or mess up or express as a twentysomething, I never got around to it. At twenty-three, I was diagnosed with a malignant teratoma, a quick-growing tumor composed of cells that can take the shape of teeth, hair, bone, intestinal lining, even a half-formed eye. “Teratoma” comes from the ancient Greek τέρατα, meaning “monster,” and when it was cut from my body two months after I first noticed it, it was — to borrow my oncologist’s phrase — the size of a viable fetus.

Now, later in life, I remind my sons at bedtime every night that monsters are not real. “I know,” says my firstborn, the one most terrified of the dark. “But why are they so much bigger than us?”

This is the boy I wrote letters to in the months after giving birth, expecting I’d be dead before he was old enough to read them. There’s an awareness in him that does not come directly from me or my husband. Instead, it’s an intuition he was born with that tells him he will one day be seized, as we all are eventually, by unfathomable loss. If I were being honest, I’d tell him that I’m afraid of the dark, too. But if you let it, that fear will swallow you. Instead, I run my hand over his back and whisper, “You’re safe. You’re brave. I love you.”