He vanished on a mountain aged 12 after an argument with his dad. Now his story serves as a terrifying warning

Donn Fendler credited wild berries and a Boy Scout’s “never-give-up attitude” with his survival after being separated from his family at age 12 atop Maine’s highest peak in 1939.

They helped him through nine arduous days through the dense wilderness of Mount Katahdin, where he battled hunger, fatigue, hallucinations, insects and leeches. He even lost his shoes in a river.

Fendler’s harrowing story of survival made headlines in the lead-up to World War II, and the boy’s daring earned him an award from President Franklin D. Roosevelt.

His memoir, Lost on a Mountain in Maine, has entertained generations of schoolchildren in the Pine Tree State. Road maps, a graphic novel – and now a Hollywood film – chronicle the journey.

The film, which takes its name from Fendler’s book and whose producers include Sylvester Stallone, recreates the drama of a boy separated from his strict father, twin brother and others.

Fortunately, there is a happy ending.

Fendler disappeared from his group during a fast-moving storm as they neared the summit of Katahdin in July of that year.

He realized within hours that he was “in trouble” and he started “to panic,” he said Bangor Daily News in 2009.

Fendler went missing atop the imposing Mount Katahdin, in Baxter State Park, the highest mountain in Maine at 6,000 feet.

So he turned to his Boy Scout skills, a “never give up” attitude, his faith in God and prayers.

“It taught me to stay calm and stay calm,” he said.

He ate strawberries and blackberries and sheltered as best he could during the cold nights.

The boy followed a stream and a telephone line, which led him to a hunting camp near Stacyville, about 35 miles from where he started.

The malnourished Fendler was rescued by Maine Guide Nelson McMoarn and his wife Lena.

He was bruised, cut, hungry, without pants or shoes, covered in bug bites and 15 pounds lighter – but alive.

The bold headline of the Bangor Daily News on July 26, 1939, the day after the rescue, read: DONN FENDLER FOUND ALIVE.

Three photos of the skinny boy and four stories about him graced the front page of the newspaper.

The boy’s danger had sparked a massive search and was the subject of headlines and nightly radio broadcasts.

Hundreds of volunteers poured into the region to help; Messages of support poured in from Fendler’s parents.

In the 2009 interview, Fendler said that “prayers were sent to my mother through Western Union” from mothers across the country.

Three photos of the skinny Donn Fendler and four stories about him graced the front page of the newspaper

Donn Fendler talks to a young reader at a book signing in Bangor, Maine, in 2011. He treated hundreds of schoolchildren to his adventure story over the decades

President Franklin Roosevelt presented 14-year-old Donn Fendler of Rye, New York with a gold medal for bravery at the White House in Washington in 1940

“That’s what they did in those days,” he said.

“I guess it worked because I’m still standing here.”

His survival skills were celebrated and he attended high school, attended the University of Maine and served in the U.S. Army for 28 years.

He married Maryrose ‘Ree’ Connolly in 1953 and had four children.

He died in October 2016 at the age of 90, after personally recounting his ordeal to hundreds of Maine youth over the decades.

Schoolchildren know the saga through the memoirs he wrote with Joseph B. Egan and published in September of the same year.

Kimberly Nielsen, a teacher at Crooked River Elementary School in Casco, said her third-graders are excited about the text.

“I love that the overarching theme is that Donn never gave up,” Nielsen told AP.

‘He just never gives up. He goes and goes.’

Her teenage son learned a valuable lesson from the book: Stay together in the wilderness.

The 16-year-old was recently walking with friends in Katahdin when a storm rolled through – and they made the difficult but wise decision to turn back.

“My son wanted to continue, but he knew they had to stay together,” Nielsen said.

‘He learned that lesson from the book. I’m one hundred percent sure.’

The 98-minute film brings this wisdom and a vintage atmosphere to the big screen.

Luke David Blumm plays the brave boy, with Caitlin FitzGerald as his steadfast mother and Paul Sparks as his strict father.

Donn Fendler, 12, his feet still bandaged from his days alone in the woods, waves as he is honored in his hometown of Rye, New York.

The film Lost on a Mountain in Maine takes its name from Fendler’s memoir

The film stars Paul Sparks as Fendler’s strict father and Caitlin FitzGerald as his steadfast mother.

Stallone’s Balboa Productions took on the project because the star liked the story of a plucky underdog.

Filming took place in upstate New York, with the crew battling insects and wading through shoulder-height water for canoeing scenes.

Some scenes were shot on Katahdin and a replica of a mountain peak built into a soundstage, complete with granite stones, blowing wind, rain and lightning.

It builds on the book, using other interviews and archive material to emphasize the importance of family and faith, says director Andrew Boodhoo Kightlinger.

The filmmaker walked with Katahdin to audition for the director’s role.

Adventure stories are a dime a dozen, he says, but Fendler’s resonates because it’s “about a father and son who struggle to connect.”

“All Donn wants is for his dad to say he loves him, but he can’t because he’s a very old-fashioned dad,” Kightlinger says.

“Every day on set I remind people that we’re making a movie about a son who just wants a hug from his dad.”

The director says there are also echoes of antebellum America today.

“There are political divisions, society is a little tense,” Kightlinger said.

“Here is a film that reminds people of the power of community, the power of caring for your neighbors.”