Well, for a start, there's one more person in the country. That person will consume goods and services. That means more demand. Which means more jobs are create

Well, for a start, there's one more person in the country. That person will consume goods and services. That means more demand. Which means more jobs are created. Economies are driven by demand (consumption drives production), and economic policy is really about creating circumstances in which that demand can flourish and result in economic activity.