Jeff Kinney remembers the exact moment he realized how popular Diary of a Wimpy Kid had become.
It was 2009 and the author had just released The Last Straw — the third book in his series, which follows middle school student Greg Heffley as he documents his life in a journal. He pulled up to his book launch event at a Barnes & Noble in Long Island in New York, and was shocked at how many fans had come out to see him.
"I think there must have been 2,000 people at the Barnes & Noble and it was just absolutely overwhelming," Kinney, 53, tells PEOPLE in an exclusive interview. "My editor and I looked at each other and we knew that things had changed."
The No. 1 New York Times bestselling author recently released the 19th book in the hit series, entitled Hot Mess, on Tuesday, Oct. 22. He is celebrating with an immersive book tour across the United States and a Championing Freedom to Read initiative that sees him visiting schools and passing out free books with the support of the nonprofit organization First Book.
To reach this point in his publishing career, Kinney has to look back on the nearly two decades of Wimpy Kid taking over the world. The franchise has not only seen 19 books published since 2007 but also two video games in collaboration with the educational website Poptropica — which Kinney also created — plus a live-action movie series, a stage musical and an ongoing animated series with Disney+.
"It is really meaningful to me that people in their 20s and a little bit younger still have a place in their hearts for my books," he says. "I got to see last year for the first time, the full breadth of my readership, because we did a statue unveiling at the University of Maryland of Greg Heffley and 12-year-old fans were there, but also people who were in grad school — so 25-year-olds — and everybody in between."
He continues, "Everybody sort of acted the same way they were. They seemed excited to meet me and excited to be there for that moment. And it was really moving. Then I went right from there to the airport, where I did a tour in South America — in Colombia and Peru — and it was the same thing where people of all different ages showed up.”
Kinney says it is "really cool when you can see that whole span of the people who have read your books over the years — that's a real privilege as an author."
Now, his latest book follows Greg on a family vacation which sees extended family members coming together at a small beach house. There, "a closely guarded family secret gets exposed in a side-splitting and relatable story that is the funniest Wimpy Kid book yet," the synopsis teases.
When asked about his inspiration for the new book, Kinney says, "Childhood is such a big universe. There are always new areas to explore. One thing I realized I'd never done before was the extended family vacation, where you've got lots of people in a space that's too small for them."
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In regards to the book's advertising calling it the "funniest" one yet, he reveals that it was his aspiration from the start of writing the book. "We came up with this idea of it being the funniest book yet, and then I really held my feet to the fire and tried to make sure it was. So it was a goal and I'm really happy with the book. I think it is the funniest book and it’s the best story I've ever told."
The story lifts experiences from Kinney’s own childhood, as Greg and his family try to find the secret ingredients behind his grandma's beloved meatballs.
"My grandmother was the matriarch of our family," the author says. "And she was the matriarch because she was the best cook. She was the one who hosted all the big family holidays and everybody came to her house. And I thought, 'That's really a form of power in a way.' So, this book is all about a power struggle within the family. Everybody's trying to figure out grandma's secret meatball recipe so that they can take the reins when she's moved on."
The accompanying book show and tour — which began in Wrentham, Mass., on Oct. 20 and continues with stops in 13 cities total through Nov. 3 — sees Kinney performing in an one-hour immersive show about him "thinking about changing careers and becoming a restaurateur."
"Every year, I try to do something a little different for myself and my team," he says in regards to his tour. "We always try to innovate and create really great experiences for families, because oftentimes book events can be a little stale. I think it is easy to settle into a routine when you're an author, but I don't like to do that. I like to try to entertain."
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As for Kinney's partnership with First Book, he explains that he was inspired to take on this initiative by the increase of book banning across the country, which has helped him "come to realize how important the freedom to read is for kids."
"When a kid picks out a book, it's one of the first times that they have a real agency," he says. "And it's so important for kids to see themselves on the covers and in the pages of books they read. I think that when a kid sees themselves in a story, it's very validating."
Hot Mess is now available for purchase, wherever books are sold.