Mo Willems, children’s author and illustrator, reads from one of his books at Raymond Elementary School in 2012 in D.C. (Katherine Frey/The Washington Post)

Kids who have grown up with Mo Willems’s hilariously lovable and surprisingly sweet characters should make room on their bookshelves.

On May 3, the 25th and final book in the “Elephant & Piggie” series goes on sale. In “The Thank You Book,” Gerald (the elephant) and his pal Piggie thank everyone they know, but not before embarking on one more endearing experience. It’s the last book in a series where the two characters tackle situations ranging from cheering up a sad friend to deciding whether to share an ice cream cone.

But it’s not the last we’ll see of the pair. In September they’ll return as part of a new series, called “Elephant & Piggie Like Reading.” Here, the duo appears at the beginning and end of new easy-reader stories penned by other authors. And in October, Willems takes a new tack, producing his first cut-paper book, “Nanette’s Baguette.”

In the meantime, those looking for more Mo can check out “The Art and Whimsy of Mo Willems,” an exhibit at the New-York Historical Society, running through Sept. 25.

How does Willems — who won six Emmys as a writer for “Sesame Street,” and who garnered Caldecott and Geisel awards for his books featuring Elephant & Piggie, Pigeon, and Knuffle Bunny — continue to captivate kids? We spoke with the Massachusetts-based writer and artist to find out. Below are edited excerpts from the conversation.

Washington Post: Now that the series is ending, does it feel like the end of an era?

Mo Willems: It’s not the end of an era. I can still work with the characters but not as these books. … A teacher told me she mentioned to a student that this would be the last “Elephant & Piggie” book. He said, “That’s good, it gives him a chance to stretch his brain.” I thought, he really got it.

WP: Are you looking forward to new projects?

MW: Yes, I’m looking forward to being terrified.

WP: Will you miss writing about Elephant & Piggie?

MW: I enjoy spending time with them. I’ll still draw them from time to time, there’s always something that comes up. But they are essentially retired. I enjoy the process of making the books. Being an author you have to go out on the road and talk to people and that is great fun and exciting. But it’s about being by yourself in a room, and they were very good company.


The final Elephant and Piggie

WP: How did you come up with the “thank you” theme?

MW: I knew the last one was going to be an on-the-nose thank-you book, that they would be very gracious and thankful. And I would make sure it was funny. But it ties things together. Every character that ever appeared in “Elephant & Piggie” is in there. It’s the 25th book and it turns out there are 25 characters.

WP: How do you come up with your ideas?

MW: You don’t come up with ideas, you grow ideas. They are not wild animals that you hunt. You cultivate them. I spent many years designing and drawing and getting to know these characters.

WP: I see these characters as toddlers. Was that your intention?

MW: No! I see them as fully matriculated elephants and pigs.

WP: What do you hope readers take away from your books?

MW: It’s what they put in — what do they see and the questions they ask and what do they do after they read the books. Do they create their own stories, do they write or draw? I see it as a spark.

WP: What is the secret to your success?

MW: I’m absurdly lucky. I don’t know. I always try to think of my audience and never for my audience, and to be as respectful as I can, and if that works, that’s great.

WP: Adults love your books, too.

MW: They’re for people who haven’t learned how to be embarrassed yet. That can be any age.

WP: What’s the toughest part of writing for kids?

MW: Any writing is fairly boring and it’s a lot of work and you have to get your muscles in order, like being an athlete. You never know what to write, but you keep working and working and eventually you get to a point when you see what doesn’t work and you cut that out. There’s no way around it. Every day is a struggle to make something look like it took five minutes to create.

WP: How can parents encourage their kids to be more engaged in reading?

MW: I think reading together is awesome, no doubt about it. I think one of the things parents forget is they are really cool. So if a kid sees a parent reading or drawing all the time, they’ll think that activity is really cool. It’s not getting the kid to do something you don’t do. It’s doing it yourself.

WP: Tell me about the new “Elephant & Piggie Like Reading” series.

MW: It’s what they are reading in their retirement. These are the books they like to read. … We’ll see them start to read these good books, then go on to the actual book, then at the story’s close, make a quick comment.

WP: In October you’ll publish “Nanette’s Baguette,” which uses cut paper.

MW: I’ve built a small French village and a couple interiors, which is a new look for me. Maybe it will inspire kids to build their own village. It’s about a little girl who gets to get a baguette, her first baguette. Then baguette tragedy ensues.

WP: Uh oh, it sounds like a Knuffle Bunny tragedy.

MW: It’s bread-based. Let’s just say baguettes are a little too delicious for their own good.

 Mia Geiger is a writer in the Philadelphia area. You can find her at miageiger.com and @MiaGeiger.

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