BREATHE!
Sitting beside his bed in the infirmary she watched the dreadfully slow rise and fall of his breath. At the bottom of each exhalation was a long pause, as if his body were considering simply stopping there, as if drawing another lungful of air was just too much effort. Then she would feel the instant spike of terror in her heart... and she would agonize during those eternal seconds, until his chest began to rise again.
"Breathe!" she demanded in a whisper. And when he finally did, she would sigh with relief, and steel herself for the next time.