You stare at the ground, hoping, praying the boy will come. You aren't really hoping he'll die, except you are. Because, that's the only chance you have right now of getting back inside, of getting to your son. So you stare at the ground hoping he'll come and hoping he won't and you aren't really sure which you want more right now because it seems unfair to wish the boy death. But then, life's unfair. And he steps out and you know it doesn't matter because now the boy is a good as dead. And then, with a flash of green light and a hissing Avada Kedavra, he is.
But the Dark Lord falls too, and you can't help the brief flicker of hope in your chest as chaos reigns because no one knows what's going on no one knows what to do now. But he gets up and your heart drops into your stomach as he tells you to make sure the boy is dead. The few steps over seem to take an eternity and a second at the same time and then you're kneeling and you check for a pulse. And it's there. You ask if Draco is alive, in the castle and he whispers yes. You stand to face the crowd and announce that he's dead, and feel a tiny bit smug because you know he's still the boy who lived.
It doesn't last and the next few minute are a blur of anxiety because you're certain he'll give it away when the Dark Lord decides to make an example of him. But he stays limp and you're not sure how he does it but you're so relieved it doesn't matter. And then the gamekeeper is carrying him and you follow the others as they make their way slowly, to once more wage a war against children.