Parenting today is virtually synonymous with worry. We want to ensure that our children are healthy, that they get a good education, and that they grow up to be able to cope with the challenges of modern life. In our anxiety, we are keenly aware of our inability to know what is best for our children. When should we toilet train? What is the best way to encourage a fussy child to eat? How should we protect our children from disease and injury? Before...