From my experience, that knack is "just" such a love of the field that they are not only willing but compelled to lose themselves in the process. When you can

From my experience, that knack is "just" such a love of the field that they are not only willing but compelled to lose themselves in the process. When you can sit for hours trying to figure out some damn bug or playing the same phrase over and over and over or editing your writing to within an inch of its life, you're going to become good at it. You probably won't be the best in the world--there is certainly a gap between Mozart and Salieri--but out of 100 people who have demonstrated brilliant success in the world, 99 of them aren't those preternatural geniuses. "Just" people for whom 10 hours a day of practice is as natural as breathing. And yeah, tell those children they have passion, not talent. Praise their accomplishments as the outcome of exercising their joy, instead of a passive outgrowth of their innate ability.