Children learn what questions are welcome from the expression that appears before your answer.

Children read faces faster than words, and the flicker before you speak is the part they keep. A question met with irritation, embarrassment, or a quick glance away gets filed as a subject that costs something to raise. However careful your answer, it arrives second. Over years, that is how the list of unaskable topics gets written.

When a question catches you off guard, buy yourself a moment out loud: say it is a good question, or that you want to think for a second. Answer honestly afterwards, even if the honest answer is that you do not know.