Katherine Applegate: I'm Katherine Applegate, and I am the author of The One and Only Bob. If you've read The One and Only Ivan, you know that it was inspired by a true story about a real gorilla who lived in a mall, believe it or not, for decades And Ivan had a best friend. He's a fictional best friend whose name is Bob, a little scrappy dog with a big mouth and a big heart. I had so many readers ask me what happened to Bob and could I tell his story that I finally decided to do it.

I love writing Bob because his voice is just so distinct. He's kind of a smart aleck, and in fact, in the movie The One and Only Ivan, Bob the Dog is voiced by the one and only Danny DeVito. As I was writing Bob, I often found myself channeling Mr. DeVito's voice. He's really a fun character to write, so I enjoyed it immensely.

What I loved about telling Bob's story was going a little bit deeper into his backstory. He's a long-standing stray who is learning how to be a house dog, and how to accept love, how to deal with guilt, how to learn about responsibility — all big problems that we all face — and doing it through Bob's eyes made it an especially enjoyable experience because I love dogs.

Here's the first page of The One and Only Bob, and I think it gives you a good sense of the kind of guy he is:

Confession.

Look, nobody's ever accused me of being a good dog.

I bark at empty air. I eat cat litter. I roll in garbage to enhance my aroma.

I harass innocent squirrels. I hog the couch. I lick myself in the presence of company.

I'm no saint, okay?