"Seriously Silly! The Art & Whimsy of Mo Willems." Through Jan. 10. $12-$19.50. 10 a.m.-5 p.m. Tuesdays-Thursdays and Saturdays, 10 a.m-9 p.m Fridays, noon to 5 p.m. Sundays. Closed Mondays. High Museum of Art, 1280 Peachtree St. N.E., Atlanta. high.org.

"Knuffle Bunny: A Cautionary Musical." May 27-June 28. 11:45 a.m. Wednesdays; 10 and 11:45 a.m. Thursdays and Fridays; 1 and 3:30 p.m Saturdays and Sundays. There is only a 5 p.m. performance June 12. $15 adults; $8 children ages 6-17; free for children ages 5 and under. Combination tickets for both the Alliance musical and the exhibition at the High: $20.80 for adults, $10.40 for children ages 6-17, free for children ages 5 and under. The combo tickets are only available by calling the Woodruff Arts Center box office at 404-733-5000. Hertz Stage at the Alliance Theatre, 1280 Peachtree St., Atlanta. 404-733-5000, alliancetheatre.org.

Toddler Takeover. An arts festival designed for very young children, featuring performances of six original productions from the Alliance Theatre for the Very Young, the return of Atlanta Symphony Orchestra's Music for the Very Young, stroller tours and art-making at the High Museum of Art. Free for children age 5 and under, however a ticket purchase is required for all other guests. $30 adult day pass; $5 for big kid day pass (6 to 17 years old). Admission to "Knuffle Bunny" is included with the purchase of a Toddler Takeover day pass, but reservations are required and seats fill quickly. (3:30 p.m. May 30 and 1 and 3:30 p.m. May 31 are still available.) Get a Toddler Takeover day pass and reserve "Knuffle Bunny" tickets at alliancetheatre.org/production/toddler-takeover-2015. Woodruff Arts Center, 1280 Peachtree St N.E., Atlanta. 404-733-5000, woodruffcenter.org.

Mo Willems has created wickedly clever and funny children’s stories featuring Knuffle Bunny, Elephant and Piggie, and the Pigeon who wants to drive a bus.

With simple yet expressive cartoon drawings, the award-winning children’s author and illustrator helps young readers grapple with questions even adults must face.

He begins every book with a question, the kind of big philosophical questions children as young as 5 years of age ponder — why are people mean? What is death? And, of course: Can I drive a bus?

The stories then develop with all sorts of hilarity: the pigeon who doesn’t want to go to sleep, and then dreams about a hot dog party; the pigeon who wants to drive the bus and offers up a deal: “I’ll tell you what. I’ll just steer.”

Willems’ wildly popular work is being featured this week at both the High Museum of Art and the Alliance Theatre.

The High is presenting the retrospective exhibit “Seriously Silly! The Art & Whimsy of Mo Willems.” The exhibit will feature 100-plus works — from preliminary drawings to completed illustrations — chronicling the past 12 years of Willems’ career, which includes more than 40 books for children and numerous literary awards. The exhibit, which opened May 23, will run through Jan. 10.

And, beginning Wednesday, the Alliance will stage Willems’ children’s production “Knuffle Bunny: A Cautionary Musical.” It will run until June 28.

This marks the first time the High and the Alliance have presented concurrent visual and performing arts presentations of an artist’s work. The shows featuring Willems also will be a major attraction of the Woodruff’s Toddler Takeover (May 29–31), an arts festival for families and young children. (See the information box.)

“I am excited by this idea of it really feeling like a party — the show and the exhibit happening all at once,” the Massachusetts-based author said in a recent phone interview.

Both events, he said, help nurture his ultimate goal for his books — to not merely be read, but to be used as a springboard for creative writing and drawing. He said he always tries to make the characters simple enough so children can copy them.

“I don’t want the books to simply be consumed,” said Willems, a three-time Caldecott Honor winner. “I want them to be played. I want people to be jazzed and create their own narrative. That is how these (books) stay alive.”

At the Alliance, “Knuffle Bunny: A Cautionary Musical” is directed by Rosemary Newcott, the theater company’s artistic director for youth and families. The one-act production centers on Trixie, Daddy and Knuffle Bunny taking a trip to the laundromat. When little Trixie realizes her favorite stuffed bunny was left behind, she tries to communicate the terrible tragedy to her clueless father. “Aggle flaggle klabble!” she sobs. But he doesn’t get it.

There are plenty of hilarious scenes, including one inside a washing machine; appearances from other Willems characters, including the Pigeon; and a good ending. All the while, there are themes that resonate with people of all ages.

“I call it ‘sophisticated simplicity,’” Newcott said. “It’s amazing how he taps into what children see and hear, but us, too. The feelings of not being appreciated, the feelings of loss, and frustrations we feel across the human condition.”

“Knuffle Bunny: A Cautionary Musical” made its world premiere at the John F. Kennedy Center for the Performing Arts in Washington in 2010. (Newcott directed the production.)

Willems said that, while working on expanding and developing the Knuffle Bunny book into a musical, his thoughts changed about the book, a semi-autobiographical tale based on his life as a dad. It’s not so much about a young girl who can’t yet say her first words, he said, but instead about a parent learning to listen.

Meanwhile, the Alliance also is planning to mount a new Theatre for the Very Young production this fall, “Play the Play with Cat the Cat,” based on a Willems book series (appropriate for children as young as 18 months to early elementary school).