1860s: Children's books generally depict innocent, flawless children in innocent stories. Characters are one-dimensional and stories are strongly oriented toward teaching virtue.

Today: The Newbery Medal is awarded to Christopher Paul Curtis' Bud, Not Buddy, a story about a ten-year-old boy who runs away from his foster home in search of his father. One of the Caldecott Honor Books is Audrey Couloumbis' Getting Near to Baby, which tells the story of two sisters dealing with the death of their baby sister. Another Caldecott Honor Book is Molly Bang's When Sophie Gets Angry—Really, Really Angry, a story about a little girl's temper tantrum.

1860s: Scarlet fever, which typically afflicts children between the ages of two and ten, is often fatal, as treatments are terribly inadequate. Even when children survive, they often suffer poor health for years.

Today: Since the discovery of penicillin, scarlet fever...