I’ve always loved dogs, which puts me in a unique category along with what, maybe two or three billion people?

What’s not to love about an animal who will sit in your living room all day long, waiting for you to get home, and even if you need to work late and then stop for a stress-relieving beverage on your way home, when you unlock that front door, is absolutely overjoyed to see you? How could you not adore an animal who senses when your day is not going well and tries to cheer you up by dumping a sodden tennis ball in your lap?

I was probably 8 years old, playing in the back yard of our house in Prairie Village, KS, when my dad opened the gate and in rushed a 9-week-old Labrador puppy. I fell to my knees and spread my arms and that dog leaped into them as if we had loved each other our whole lives. It’s a scene that shows up in A Dog’s Purpose—a puppy and a boy meeting each other the very first time, both of them full of unrestrained joy.

We named the dog Cammie. She arrived in my life when I was just beginning to connect some of the dots in my memory to make a picture of who I was, forming my identity as a child. I remember every skinned knee and bicycle ride in the context of Cammie, who was always there for me. And I lost her just as I was starting to leave childhood behind, passing on after I’d spent a year in college. That’s Cammie, the dog of my childhood.

Years later I was riding my bicycle in the mountains outside of Pine, CO. A chance decision to bounce down a dirt road led me past a few scattered ranches and one small house near a creek, set back from the road at least 50 yards. A single “woof” from a dog caught my attention, and I braked and stood in the dry, clear air, regarding the dog who had called out to me.

She was on a chain by the house, and a fence stood between us, so I remained on the road even though I could see that the dog, a black lab mix with a crazily active tail, was clearly friendl