Author John Green Reveals the Phillip Roth-Inspired Rule That Keeps His 18-Year Marriage Strong (Exclusive)

The 'Paper Towns' author and his wife, Sarah Urist Green, first met in boarding school and have two kids, ages 10 and 14

After nearly two decades of marriage, John Green and his wife are as strong as ever — and he isn’t shy about why!

At a screening of the film Turtle’s All the Way Down — which is based on John’s novel of the same name — the author opened up about his marriage to wife Sarah Urist Green, and how the two are still so happy 18 years after saying “I do.”

When asked about rules that have helped guide their relationship over the years, John, 46, had a simple answer.

“We just care about each other a lot,” he tells PEOPLE of Sarah, who posed by his side at the premiere.

Related: John Green Blasts Indiana Library for Removing 'The Fault in Our Stars' From Young Adult Section

The young-adult novelist also recalled a tidbit about love he gleaned from fellow author, Philip Roth, in his 2000 novel The Human Stain. “There's a great line in a Philip Roth novel where somebody says, ‘It's not about owning the person, it's about having a contender in the room with you,'” Green explains. “And for both Sarah and me, we are each other's contender in the room.”

John and Sarah — who share two kids, son Henry, 14, and daughter Alice, 10 — first crossed paths at Indian Springs School as teens, but did not begin dating until years later.

As John’s TikTok-famous brother Hank Green explains in a 2010 video announcing Henry’s birth on their shared YouTube channel “vlogbrothers,” the Looking for Alaska author took “little notice” of his now-wife at the time, Years later, he recalled, "Well, I think I thought she was kind of cute."

Related: Beloved YA Books That Have Been Adapted Into Films

“Sarah, on the other hand, quite clearly remembers the charmingly nerdy upperclassman, though their interactions were few,” adds Hank.

After graduating from the Alabama boarding school, it took about a decade for the pair to cross paths again. At the time, Sarah was living in Chicago and learned that her friend and sparring partner had previously dated John.

Shortly after, they reconnected, began emailing and then dating in 2004. A year later, John proposed and they tied the knot in Alabama.

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The couple of 18 years keeps their relationship private, although John has shown support for Sarah on his social media. In 2020, he ended an Instagram hiatus to promote her book, You Are An Artist.

"It’s a fascinating book filled with creativity prompts from all kinds of artists,” he wrote, at the time. “For me, the book has been a real balm amid the fear, helping me to pay closer attention while making stuff for and with people I love.”

The couple has also hit several red carpets together over the years, including at the premieres of John’s book-to-film adaptations The Fault in Our Stars and Paper Towns.

Following the premiere of TFIOS in 2014, John shared a photo of the couple on Instagram and wrote, “So special to share this with the love of my life."

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