A GENERATION FROM NOW, people will still talk about the way Bradley William Stone went about butchering his ex-wife and her family, leaving a trail of blood and gore across Montgomery County as he moved from house to house, town to town, ambushing them in the middle of the night like a demon from hell.

But no matter how many times the story is revisited, no one will ever be able to answer the question that gnaws at the soul of anyone who discovers all of this heartache and horror: Why?

Any hope of making sense of the Monday morning massacre that claimed the lives of Nicole Stone and five of her relatives was snuffed out yesterday afternoon, when investigators found the killer's body in the woods in Pennsburg, about a half-mile from his house.

Brad Stone, 35, committed suicide, apparently hacking away at himself in his final moments with a knife, District Attorney Risa Vetri Ferman said.

The discovery of his body brought an end to a manhunt that had left the area increasingly on edge as authorities struggled to pinpoint Stone's whereabouts.

Those who were friendly with Stone and his ex-wife, meanwhile, were left with the impossible task of trying to reconcile the guy they thought they knew - a father who adored his two daughters - with the cold-blooded killer whose fury made national headlines.

Military veterans who served with Stone in the Marines recoiled at media reports that seemed to link the bloodshed with Post Traumatic Stress Disorder that Stone was supposedly saddled with from a tour in Iraq.

"A lot of us come home with it, but you can't blame what happened there on PTSD," said a veteran who once worked alongside Stone. "It really is the person you are underneath that will decide if you do something like this."

'See the tension'

At Back to School Night, Girl Scout functions, evening pickups at after-school recreation, Brad Stone appeared to be the ever-present father, "doting" on his little 8- and 5-year-old girls, often dressed in a suit and tie, said Gwen Hemmig, 57, whose granddaughters attend the same Souderton-area elementary school as Stone's children.

"He was just always there. Always helping with craft projects and always smiling. You could tell he was very proud of the girls," said Hemmig, who saw him recently at a Girl Scout "songfest" held at the local high school.

"At the songfest, he's in a lot of the pictures with the girls," Hemmig said. "He was always very sweet and pleasant . . . He seemed to be a sweetheart."

Stone and his ex-wife, Nicole, seemed to share a deep love for their kids, and a palpable dislike for each other, Hemmig said.

"A lot of times he and Nikki were both there - on opposite sides of the room," she said. "You could see the tension between them when they would be in the same room together."

Stone brought his new wife, Jen, to this year's Back to School Night, Hemmig said.

Aside from their ongoing custody dispute, Stone and his ex-wife had evidently moved on with their lives, with Nicole recently getting engaged and Stone remarrying in September 2013. His Facebook page features a wedding photo in which Stone clasps his wife's face in a kiss.

"The smile still hasn't gone from my face," he posted beneath the photo on Sept. 16, 2013.

"I love you so much Mr. Stone," replied Jen Stone. The two had an infant son.

Yesterday, Jen Stone's co-workers at Field Marketing Solutions, where she is a media analyst, declined to comment, other than to say that it's "a difficult time."

Jen Stone did not return a phone call from the Daily News.

'A substandard Marine'

Underneath the cheery face that Stone put on in front of others lurked a more troubled man.

He'd been on probation for the last year, having pleaded guilty for the second time to driving under the influence of intoxicants, according to court records.

Bucks County District Attorney David Heckler said Stone had received psychiatric treatment at the Lenape Valley Foundation in Doylestown Hospital. What he was treated for was unclear.

Doylestown briefly served as a focal point in the hunt for Stone after a resident claimed late Monday that a man in camouflage had tried to rob him of his car keys at knifepoint. That lead fizzled.

Ferman said Stone was denied emergency custody of his children last week but had not, to her knowledge, been diagnosed with PTSD.

Stone was discharged at the rank of sergeant from the Marine Corps Reserve in 2011, military officials said, and spent less than three months in Iraq in 2008. His military occupational specialty was listed as "artillery meteorological man."

A Marine veteran who was assigned to the 3rd Battalion, 14th Marine Regiment - the same unit as Stone - recalled Stone in less-than-flattering terms.

"He wasn't what you would call a good Marine," said the vet, who recently came home from deployment in Afghanistan, and didn't want his name used because he didn't have permission from the military to talk about Stone.

"I thought of him as a substandard Marine," he said. "He physically didn't meet our standards, and he was more interested in having the title of being a Marine than in doing the work it required."

The veteran said Stone's tour in Iraq didn't last long because he convinced superiors that he had asthma and needed to go home.

"Everyone keeps reporting that he had PTSD, but that really puts a bad taste in the mouths of former Marines who were overseas and actually served their time," he said.

He and Stone didn't serve in Iraq at the same time, he said, but worked together for about six months at the regiment's Philadelphia-based headquarters.

"There was always something off about him. He was always arguing with his wife on the phone," he said.

Eric Zillmer, a professor of neuropsychology at Drexel University who authored a book on military psychology, said it was doubtful that Stone's killing spree could be blamed on PTSD.

"It is stressful to go to war, no question, but a lot of people who go to war don't develop PTSD," he said. "Or, if they do, they don't go on a rampage and kill six people."

'Mommy, no!'

The first hint of the nightmare came at 4:25 a.m. Monday in the form of a 9-1-1 call from the Lansdale home of Nicole Stone's mother, Joanne Gilbert, and grandmother, Patricia Hill.

The caller hung up without saying anything. Police went to investigate and found Gilbert, 57, on a bed, and Hill, 75, on the floor, both with blood pooled around their heads, according to an affidavit released by authorities.

Gilbert's throat had been slashed, while Hill had been shot in the right eye.

A half-hour later, police in Lower Salford Township got a 9-1-1 call from the Pheasant Run Apartments, where Nicole Stone lived.

According to the affidavit, a neighbor, Ashley Deane, heard glass breaking and then a loud bang in Stone's apartment, followed by three or four gunshots.

Deane heard Stone's little girls cry out: "Mommy, mommy, no! I want my mom!"

Deane looked outside in time to see Brad Stone loading his kids into a green Ford as he uttered these chilling words about his ex-wife: "She's hurt, we have to go. She's hurt." Stone later dropped his daughters off unharmed at a neighbor's house in Pennsburg.

Nicole Stone was found dead in her bedroom, with two gunshot wounds to her face. Her ex-husband's .40-caliber Heckler & Koch handgun was on her bed.

Investigators realized the three killings were related, and turned their attention to the Souderton home of Nicole Stone's sister, Patricia Flick, her husband, Aaron Flick, and their two teenage children, Nina and Anthony.

About 7:45 a.m., police entered the Flicks' house and found a horrific scene that had apparently been the starting point of Stone's rampage three hours earlier.

Nina, 14, was found dead of blunt-force trauma and lacerations to her face and skull in her bedroom. Patricia and Aaron were also dead in their bedroom; Patricia had been shot in the face.

Anthony, 17, remarkably survived a gruesome assault - a gaping skull fracture to the back of his head, numerous lacerations to his arms and several missing fingertips. He was listed yesterday in serious condition at Thomas Jefferson University Hospital.

Ferman said it appeared the teen's injuries came as a result of trying to fight off Stone.

All day Monday, heavily armed cops in tactical gear staked out spots where they mistakenly believed Stone had holed up - first, the Flicks' home in Souderton, and then Stone's own house in Pennsburg.

Officers still stood guard outside the Stones' two-story, brick twin on 4th Street yesterday. Police had knocked down the front door and bashed the garage door to bits Monday, when they thought Stone may be hiding out inside.

Yesterday, passers-by could gaze inside unimpeded. Off a front porch with matching rocking chairs, the living room appeared ready for holiday revelry. A half-decorated Christmas tree stood in the corner, beside a chewed-up rawhide bone in a dog bed and a packed bookcase.

By an alley beside a neatly landscaped backyard, the garage suggested the family's pack-rat tendencies: Bicycles, wagons, patio furniture and a green US Marine Corp. box lay in a jumble inside. A child-sized plastic slide and basketball hoop stood on the patio.

Many tried to make sense of Brad Stone's crimes, and even sympathized with him, figuring deep-rooted mental problems were to blame for the massacre.

SWAT and K-9 cops began sweeping the area again in the afternoon yesterday, leading them to find Stone's body shortly before 2 p.m. in a wooded area not far from his home. Ferman said it appeared that Stone died of "self inflicted cutting wounds" to the center part of his body.

Hundreds gathered last night at a vigil for the victims inside Emmanuel Evangelical Lutheran Church in Souderton.

"Many will ask, where was God?" said the Rev. Heeralal "Mukesh" Cheedie.

Some in the crowd left the church, exhaling in the vestibule as if they'd been holding their breaths, and headed back out into the mist outside.

-Staff writer Vinny Vella contributed to this report.

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