Roald Dahl wrote some of the world's most beloved stories. Such works as "Charlie and the Chocolate Factory" and "James and the Giant Peach," both written in the early 1960s, have never fallen out of favor with each passing generation of children.So when Mark West - a professor of English at UNC Charlotte who specializes in children's literature - had the opportunity to spend a day with Dahl in the 1980s, he made sure to lean in close as the elder whispered a crucial secret of his literary success.It wasn't what West expected to hear from a children's author."He said, 'Mark, the first thing you have to do when you're writing a kids' book is kill off the parents.' "That's a startling statement, but it's a common practice among writers of kiddie lit. Thumb through the childhood favorites of every era and an unnerving theme will begin to emerge: "Oliver Twist," "Tom Sawyer," "Anne of Green Gables," "I Am the Cheese," "The Outsiders," "Harry Potter."Where have all the parents gone?In fiction, orphans are free from the reins of their parents. They're able to dive headfirst with reckless abandon into any situation they see fit, no questions asked.It's really very simple, said West, for the reasons children like stories with orphan protagonists."Kids like a sense of adventure, and they like kids being able to do things without meddlesome adults."Tom Sawyer's parents certainly wouldn't have let him sneak around graveyards at midnight or explore a cave that doubled as a seething murderer's hideout. And using a dead cat as a cure for warts probably would have led him to a couch in a child psychiatrist's office.But there was a time when children's literature wasn't completely devoid of parents. In the 1800s, most children's books were written to teach children lessons, not entertain them with tales. On each page, parental characters delivered instructions on how to behave properly."In 19th-century children's literature, the stories were kind of the sugar to help the medicine go down," said West. "The story wasn't the thing."That didn't exactly add up to page-turners for kids. But books, a luxury back then, were not bought by kids, either. Parents made the purchases, and the publishers fed their demands eagerly."If you're publishing books for children but you know adults are going to be the ones who purchase them, then what you're really trying to do is appeal to the adults," said West.A few trailblazers broke through, but not without initial uproar."In the 19th century into the early 20th century, librarians hated 'Tom Sawyer,' " said West. "They thought it was a terrible children's book."A young character constantly outwitting authority figures grated on adults' nerves like nails on a chalkboard.Later, when children began to hold some of the purchasing power themselves, publishers began to cater to them as well.Dime novels, cheap paperbacks that kids could afford, detailed high stakes adventure in their storylines and became instant hits.That tradition continues today with authors like J.K. Rowling and her stories about the adventures of an orphaned wizard."It's kind of like a renaissance of children's literature," said West. "The tremendous success of Harry Potter books, of which there's been no parallel, will show that children in some ways are coming into their own as an economic force."