News of the kindness exhibited in the close-knit community comforted Kozel's mom in the long months that she was gone. Mary Kozel was as OK with her daughter hiking the Appalachian Trail as a mom can be. After a lifetime of seeing her daughter overcome challenges, Mary was prepared for an adventure as audacious as this one. Still, the thought of her paralyzed daughter alone in the endless wilderness scared her. It didn't help that all the stories people told Mary about the Appalachian Trail had bears in them. "They thought it was funny," she says. "I didn't."

Kozel's first bear scare came just a few days into her hike. As she lay in her tent, her braces standing in the corner, she thought about all the warnings about bears, and how she hadn't seen any, and how the hype hadn't amounted to anything. Suddenly, she heard a rustle, her heart leapt into her throat and she thought a bear was about to rip her to shreds.

Her scream echoed through the woods.

Then she realized the rustle was just the noise of her braces falling over, and she was worried her scream of terror had ruined other hikers' peaceful evenings.

"I was like, 'SORRY! ... Sorry ... sorry ... sorry ....'" she says.

Weeks later, as Kozel hiked with her "trail family" in Virginia, she turned a corner to see a mama bear and two cubs. Hiker code says not to run, but to make yourself as big as possible and make a loud noise to scare the bears away. Her companions turned around and ran. Kozel's paralysis makes it impossible for her to turn around quickly, never mind run, so she crossed her poles across her chest and made a noise that she intended to be a yell but that came out sounding like a squeak. It should not, she says, have scared a bear. The mama bear and her cubs backed off.

When Larry Schulte (trail name, Windy, because he talks so much) saw Kozel and her braces on the trail one day, he thought of his own ACL surgery. He asked if she was recovering from a similar operation. When she said she was paralyzed, he blurted out, "That's awesome!"

What he meant to say was that it was awesome that she had the courage to hike the trail. He found her inspiring and became her evangelist on the trail. News about Kozel flowed north and south, blown in each direction by conversations at campsites and shelters where hikers stopped for the night. She became "trail famous." Kozel's trail name, Iron Will, only hints at the esteem with which her fellow hikers view her.

Part of what makes the trail fun is complaining about how miserable it is. Kozel's name came up often in that context. "We were done and tired, bitching about that stupid boulder field, or somebody needs to turn down the heat," says Gabe Burkhardt. "Somebody would arrive in the middle of one of our bitch-fests and say, 'I just saw Iron Will, and she was huffing through this same boulder-field stretch, and she was doing it.' That usually made our bitch sessions a little bit shorter. Not much. But a little bit."

The more Burkhardt, a vascular and trauma surgeon who retired as a major from the Air Force in 2013 after more than 20 years, heard about Kozel, the more he hoped to catch up to her and meet her. He had spent years researching soldiers' use of prosthetics and "ambulatory assist devices" -- the fancy way of saying braces.

He was curious to see how Kozel used her braces and how well they worked (or didn't). He finally caught up to her in New York state, just after the summit of Bear Mountain. He watched her walk with a clinical eye. He saw that the braces made her gait stiff and uncomfortable, but he also saw that they weren't doing any harm to the rest of her body -- a critical piece of analysis when measuring the value of any such device.

Think of walking as a controlled fall. You lean forward, and just when you're about to tumble onto your face, you swing your leg out and catch yourself. Kozel's hip muscles allow her to swing her legs forward. But she has no control over muscles any lower than that. She can't bend her knee or foot, and her leg muscles don't work.

She has two sets of braces. Both stabilize her knees, feet and ankles. Neither "walks for her" at all. One is made of metal and allows her to walk stiff-legged. The other is battery-powered and has computer sensors that tell the braces what angle her knee and foot should be based on her stride.

The stress on her upper body means she expends roughly twice as much energy as an able-bodied person in covering the same distance, says Joey Pollak, the prosthetist and orthotist who outfitted Kozel with the braces.

In everyday life, the battery-powered braces, which have to be recharged every two days, allow nearly normal walking. But there is no normal walking on the trail, and the high-tech braces malfunctioned frequently. When the batteries ran out, the braces worked like the simpler ones, except they were so heavy that Kozel felt like she had cement bags strapped to her legs. Still, Kozel hopes her long hike with those braces proves to insurance companies reluctant to pay for them that they are valuable.

That was all impressive to Burkhardt from a medical perspective. But it's not what impressed him most about Kozel. "After about five seconds of talking to her, she's got this big, beaming smile on her face," he says. "Seeing how happy she was, and how fulfilling this was for her, and how much of a challenge it still was, it was incredibly inspiring for me."

Burkhardt and Kozel only spoke for a few minutes, and they followed each other in the coming weeks via social media. When Burkhardt (trail name: Sketch) complained on Facebook, Kozel always chimed in with support. He marveled at that -- he's just some guy walking the trail, and here she is, encouraging him to keep after it. "That, by itself, I thought was phenomenal," he says. "I'm looking forward to trying to emulate her example."

Up and down the trail, Kozel left inspiration in her wake. Burkhardt said other hikers were jealous that he got to meet her, and another thru-hiker said he heard so much about her he was bummed he never ran into her. Kozel blushes at all of this, saying, "I'm just another hiker stumbling through the woods."

Sharing the story of her hike became a big part of why she wanted so desperately to complete it. For years after she was diagnosed with lupus, she rarely told people about it, instead making up other excuses when she was ill. As her attempt to complete the trail became publicized -- she's appeared on the CBS Evening News and in The Washington Post and numerous local TV and newspaper stories -- she saw how it inspired people.

Her Catholic faith is an important part of her life, and she wondered during her lupus flare-ups what God wanted to teach her through her struggles. She concluded that using the hike to encourage people would give her suffering the meaning it had lacked before.

There are three ways to complete the trail. One is to "section hike," which is to return year after year until done. Another is to "thru hike" -- start at one end and walk straight through to the other. A third is called "flip flopping," which is thru hiking, only not in linear order.

In late August, Kozel decided to flip from Vermont to Katahdin, then flop back to Vermont. It sounded like a great plan. But it didn't work.

The hike up Katahdin is widely considered the most difficult stretch of the entire trail, and she wanted to complete that before it got too cold. Elevation at the summit is nearly a mile high, and getting to the top is difficult, even on a good day. She simply didn't have one. Her attempt to climb Mount Katahdin was beset by problems with her braces, swelling in her legs and feet, and boulders so big that scaling just one of them took her an hour. She hadn't felt well for some time, and she was worried another lupus flare-up was starting.

In the midst of those struggles, a ranger at Baxter State Park, which contains Katahdin, offered to charge Kozel's braces if she would use the power to walk down the mountain instead of up. The ranger told Kozel that if she had to be rescued, she would have to pay for it. Kozel found that both discouraging and insulting.

"If I thought I was going to endanger rescue crews, I wouldn't do that," Kozel says. "That's why that kind of upset me. Just because I'm disabled and have lupus doesn't mean I can't do this. I want to help people. I don't want to injure people. I want to change the view of people like her who think because I'm disabled I can't hike this mountain."

Another ranger gave her a written warning about camping on the trail. She wasn't camping, but she was going so slowly while hiking through the night that it seemed like she was.

(A few words in defense of the rangers who sound so cold -- it's not necessarily fair to say the rangers singled Kozel out for discouragement. In the name of safety, they discourage everybody. Research Katahdin, or talk to rangers there, and you'll find so many dire warnings of its dangers that climbing it sounds like the dumbest idea anybody has ever had.)

After four days and 60 hours of hiking, Kozel decided to abort the attempt. As she made the slow walk down -- retracing steps that hadn't advanced her goal, spending time she didn't have and expending energy she couldn't afford to waste -- she thought she had proved the rangers right instead of wrong. "I want people to not give up, whatever they're going through," she says. "And I was giving up."

She tried again a few days later and got to an area known as Thoreau Spring -- a mile from the summit -- but had to turn around again, this time because of lightning. That made three failed attempts at Katahdin (she had hiked there in October 2015 before she was sure she was going to attempt a thru-hike.) Pressed but not crushed, she returned to Vermont, determined to regain her momentum and take one more shot at scaling Katahdin. "There was no way I was quitting," she says. "Forget that."

Katahdin haunted her steps from Vermont, through New Hampshire and into Maine. There is a delicate balance here, between drive and obsession. Nobody whose opinion is worth listening to would think 2,189.1 miles was great but 2,188.1 was unworthy. Kozel acknowledged this ... sort of. But she sees it as binary, pass or fail, with no in-between. Yes, walking 2,188.1 miles alone in the wilderness while paralyzed was a great accomplishment. But she had set out to walk 2,189.1. She is not the type of person to set a goal and be content to come close to it. She yearned to pass every blaze, to prove right the people who believed in her. She wanted to show people facing struggles that they could accomplish whatever they wanted. If she left that last mile un-walked, she could not rightly say that about herself.

An internal fire drove her, too. Lupus, she said, had robbed her of the ability to play sports. It had disrupted her career and education multiple times, and her flare-ups always seemed to come just as she was about to finish something important. She was about to finish something again, something big and incredible and inspiring, and she refused to let lupus stop her.

So much of Kozel's story is about attempting the impossible instead of settling for the simple. It would have been easy for Kozel to disappear into her home after she was paralyzed. That's what her mom said she would have done. But Stacey would rather try something hard. We spend so much time worshipping comfort that somebody who doesn't bow at that altar sounds heretical. We have turned discomfort into something to be avoided rather than endured and conquered.

Not Kozel. If she got cold, she could warm up. If she got exhausted, she'd recover. But if she quit, she'd regret it for the rest of her life. She used the long, arduous stretch from Vermont to Maine to prepare herself, mentally and physically, for Katahdin.