Antoinette Portis’s debut picture book, Not a Box (2007), was a Theodor Seuss Geisel Honor Book, and her six subsequent titles have appeared on bestseller and “best of” lists. She was awarded a Sendak Fellowship in 2010. Her newest title, Wait, is an affectionate look at a mother who’s in a hurry and a toddler who says “Wait!”

Is Wait based on a memory from your own childhood, or an experience you had as a parent?

Neither! I was waiting for a friend in a café when I saw a mom and little boy walking along, and the boy stopped to look at a bug that was on the windowsill. You know how it is, their arms are so short – when the mother dragged him away, he was lifted right up onto his tiptoes. He was still looking back at the bug, and I thought to myself, “That is a book!”

It’s a delicate story to write, isn’t it? You have to make it clear that the mother is not the bad guy.

That’s right. I’ve been working with a group of writers for eight or nine years now, and when I showed it to them, they said, “But the mom is the jerk! It’s just going to make moms feel bad!” We all know parents have to rush. It’s a given of life. I’m a mom and I’m sure that my daughter has memories of me not accommodating her every wish. The key was finding a reason for her to be rushing, and the train they have to catch at the end kind of paid it off. Everybody can relate to that – everybody hears the rumble of the subway and starts dashing down the stairs, even though they know there’s another train in seven minutes.

In earlier versions the story ended a bunch of different ways. In one version the boy found a dandelion in the sidewalk and gave it to her. In another, the mom dropped her watch, and the boy found it because he was the only one who was looking at the ground – he was the only one who was paying attention.

The mother and the boy have brown skin and darker hair instead of lighter skin and hair. Did they appear in your mind that way, or did that evolve?

I knew I wanted to do that from the beginning. I take the work of groups like #WeNeedDiverseBooks seriously. We’re in Los Angeles, and many of the kids in my daughter’s class were from different places or different backgrounds – it was this rainbow of children. Every kind of kid was there, and the kids didn’t notice. I wanted to reflect that.

You worked on the book with Neal Porter at Roaring Brook. Did the story change very much after it got to him?

It was pretty much complete by the time he saw it. What he mostly did was cut stuff; I had way too much material, and he picked the scenes he liked the best. There was a bakery scene that got cut. But we left the cement mixer in – we had to keep that! We needed a boy thing.

I haven’t developed a book from scratch with Neal yet because I’m working my way through a backlog; I have many stories I’ve spent months working on with my writing group already. But I’m looking forward to getting to a place where I can hash out a story from the beginning with him. I’m hoping I can work with Neal forever. There are awards for authors and illustrators, but I think editors should get awards, too!

I love the picture book form so much – what you can do with it, the power of it. I’ve been in the business for 10 years. I’ve been trying to manifest what I know about it, and I feel like in Wait I finally got there. Everything I know is in it.

Wait by Antoinette Portis. Roaring Brook/Porter, $16.99 July ISBN 978-1-59643-921-4