I knelt down beside the bed so that my face was level with hers.

“I am never disappearing on you again,” I said.

“Not ever.

And listen to me, because this is a rule now, in our life, forever: if I ever have to leave a room, you will always know just where I am going, and just when I am coming back.

You will never again have to wonder.

Do you understand?” She studied my face for a long moment, checking it, the way I had learned soldiers check a bridge for weight before they cross it.

And then, slowly, she nodded, and closed her eyes.