[It almost sounds like she's approaching this question from a position of power. If that's the case, then perhaps the costume isn't exactly just for a school play? But he won't pry. He's fairly skilled at getting people to talk about what they don't want to talk about, and it's unfair to do that to a grade schooler just because he's curious.]

More people fighting doesn't usually result in fewer people getting hurt. Please be careful. The people in charge of this place might benefit if we fight for them, so we can't take their word for it that we're on the right side.