Mark Hamill and Wife of 47 Years Marilou Reveal Their Two Marriage Rules (Exclusive)

Nearly 50 years after tying the knot, Mark and Marilou Hamill know a thing or several about what makes a marriage work. 

After meeting in the mid ’70s at a dental office where Marilou worked as a dental hygienist, the couple wed in December 1978 at their home in Malibu, Calif.

Now, almost five decades and three kids later, Marilou tells PEOPLE that from her experience, when it comes to marriage, “Don’t sweat the little stuff.”

“And also, go in knowing you’re not going to change anyone. So you have to accept their quirks and their behavior,” Marilou adds before Mark humorously interrupts: “What quirks?”

Mark agrees, saying it’s both about “acceptance” as well as “communication.” 

“I just think that when you find the right one, the odds are against you,” the Star Wars actor adds. “But if you do get lucky, you just have to hang on and be grateful that you were able to find that one.”

The Hamills shared their marriage advice during a recent conversation with PEOPLE about the new documentary Big Rock Burning, which the couple executive produced. The two reflected on their community of 47 years — the Big Rock neighborhood in Malibu — and the home they had to leave amid the L.A. wildfires earlier this year. 

“We got married there, We raised our kids there. It’s a very, very special property,” Marilou says.

The film, which had an exclusive preview screening hosted by the Malibu Film Society and the City of Malibu on Aug. 29 at Malibu City Hall, tells the stories of those in Big Rock who were “left to face the fires alone,” per the opening credits of the film, and includes devastating footage of the rubble left where homes once stood. 

The documentary’s focus is largely how Big Rock’s residents feel their local government was negligent in their preparation for the natural disaster. And, once the fires made it to their neighborhood, they say there was no emergency response as the area was considered too dangerous.

While their home is still standing, the Hamills have yet to return as “it’s toxic with chemicals,” Mark explains. 

“I’m so thankful and grateful that our house survived,” Marilou says. “But I just didn’t realize the ramifications of it.”

Big Rock Burning, which has a producing team that includes Julie Parker Benello, James Costa and executive producer Ricki Lake, will have an Oscar-qualifying theatrical run from Sept. 12-18 at the Laemmle in Santa Monica.