Our kids implicitly understand this thing called the sunk st fallacy better than parents. A rational person knows that what went into something, what you paid for it, is irrelevant the second after it happens. But a responsible adult, we can't seem to forget all of that. Our kids show us how to embrace change and chase our interests. Let them loosen you up. Follow their lead. Don't get stuck in your ways. Remember, courage is calling for favors.