"I've learned that I'm a children's writer," he says. "I didn't know it when I was starting off, but I know it now."
Jeff Kinney marks 10th anniversary of 'Wimpy Kid' series →
"My 5-year-old makes it clear to me that my books are not his favorites," Mr. Kinney says, laughing.
'Wimpy Kid' author keeps day job on kids' website →