A child’s question deserves an answer that does not punish curiosity for its timing.

Questions arrive at inconvenient times because a child asks when the wondering happens, not when the room is ready. Meeting that with irritation teaches something the answer never could, which is that curiosity has a cost and the safest thing is to stop bringing it. What gets learned is about you, not about the subject.

Say plainly that it is a good question and that you cannot answer it right now. Give a time, and come back to it without being reminded. Even a short honest answer later keeps the asking alive better than a full one that never comes.