Author of 'A Dog's Purpose' Reveals Story Was Originally Written to Help Ease Girlfriend's Grief

"Her dog Ellie passed away. It was the first dog she ever had, so she was completely unprepared the way the grief overwhelms you," Bruce Cameron explained.

As the award-winning novel A Dog's Purpose makes its debut on the big screen, the author is opening up about the motivation behind penning the story.

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Los Angeles author Bruce Cameron told InsideEdition.com it all started when his girlfriend at the time, Cathryn Michon, lost her dog.

"Her dog Ellie passed away," Cameron said. "It was the first dog she ever had, so she was completely unprepared the way the grief overwhelms you."

She then vowed never to adopt another dog.

At the time, Cameron explained their relationship had started to become serious, and Cameron, who has had a dog ever since he was 8 years old, said he couldn't imagine not having a canine in his life.

To ease her grief, Cameron said, "I told her a story about a dog that reincarnates, and remembers each life and eventually comes to conclude there must be a reason, a purpose, it keeps being born. Until it figures it out, it keeps being reincarnated."

The author eventually put pen to paper in a retelling of the story that eventually became The New York Times bestseller, A Dog's Purpose.

Today, Cameron and Michon are married, and as co-screenwriters, the tale is headed to theaters January 27.

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More importantly, Cameron said his attempts at cheering up his significant other worked. The couple eventually came to adopt another dog, Tucker, which they rescued from euthanization seven years ago.

The hound even acted as the ring bearer to their wedding as a puppy.

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