Steve Cunningham never should have gone ahead with that fight. Not then, the first week of April. His opponent, Amir Mansour, was from Delaware but trains in Philadelphia. Cunningham hated fighting other Philly guys. Their city was supposed to conquer the boxing world, not get mired in civil wars. Also, Mansour was a true heavyweight who would enter the ring close to 20 pounds heavier than Cunningham, who was 37 at the time and had spent most of his career below 200 pounds at cruiserweight. Since coming up, Cunningham had struggled to keep the weight on. He’d been the smaller man in every bout. He’d taken hits — brutal, dirty hits, the kind of blows no cruiser can deliver. He’d lost. Twice. And now, here in Philly, he was about to lose again.

Before the fight, his wife, Livvy, knew: This might be it. One more loss and Cunningham’s career might be over. Maybe he’d get other chances. Maybe not. But even if he could fight, after all this, would he? “I love boxing,” he sometimes told her. “But I’m still waiting for boxing to love me back.”

Cunningham’s trainer had suggested they call it. We can back out. We don’t have to do this fight. He’d said this after he heard that Cunningham’s daughter, suffering from a heart ailment, might not have much time to live. But Cunningham said no. I’ll be OK. I’m good. “I don’t care about you!” the trainer, Naazim Richardson, who had recovered from a debilitating stroke in 2007, told his fighter. “With all this going on, we need to call this thing off for me!”

But here was Cunningham. In Philly fighting a Philly heavyweight, his daughter Kennedy sitting in Livvy’s lap on the front row. In the fifth round. He’d already been knocked down once, just seconds ago by a right hook, and now Mansour was backing him into the ropes, threatening to cut him down again.

Mansour threw a right hook. Cunningham fell back into the ropes, but stayed on his feet. While Cunningham took a moment to regain his balance, Mansour wound up and hit him again. Wobbly now, Cunningham ducked. Too slow. Mansour came with the right hook again. The punch brought Cunningham to his knees, to his back, to the mat.

“Get up, Steve!”

They’d saved their money. If he stayed down they might be just fine. Livvy could find a decent job. Steve could look for TV commentating work. Their family of five could survive without boxing. The only problem was the medical expenses. Insurance covered Kennedy’s care, but if they wanted to exhaust every option for saving her life, they would need to travel. They might even need to move. These things cost money the Cunninghams didn’t have.

“Come on, baby, get up!”

Livvy could see his eyes. He was there. He was listening. He would get up — she just knew it. Kennedy could see him, too, but unlike her mother, the 8-year-old girl couldn’t scream. A tracheotomy had left a hole at the base of her neck. Her voice was too thin to reach the ring. And besides, Kennedy could never get too rowdy or energetic. Her heart was too weak. Excitement was too dangerous.

But months later, sitting in an apartment in the new city with the new hospital that she believes will save her life, Kennedy, now 9, looks up from her iPad to explain what happened next.

“He looked at me,” she says.

“He looked at you?” Livvy asks.

“Yeah. Didn’t you see it? He looked at me and then he got up.”

David Spagnolo

Decades earlier, as a 14-year-old growing up in Philadelphia, Cunningham threw his first punch. He’d been getting jumped by neighborhood kids. He’d always taken it. Better to give them what they wanted than to fight back. But one day at school, another kid tried to fight Cunningham in the middle of class. The teacher ran to get help, and both of them were taken to the hallway, and when the kid came after Cunningham again, he finally decided he’d had enough. “I traaaaaaaaaashed him,” Cunningham says. “Just laid him out.”

Cunningham watched the other kid fall. He stood over him. He thought: I can do that? Like, I’m capable of putting somebody on the ground like that? From then on, when other kids hit Cunningham, he hit back. Soon enough, word got around. People stopped jumping Cunningham.

His childhood was “perfect,” he says, “up until my dad started beating on my mom.” She moved out and took Steve with her. His dad started using crack. He and his mom bounced around town without a home. Once they found a place to stay, life improved, but just a little. By the time Cunningham approached ninth grade, he spent more time on drug corners than at home.

He wanted a pair of Jordans, so he sold crack until he could buy them. He wanted to take girls to the movies, so he sold more crack and then he did that too. His mom worried about him. But one day she was short on rent. She needed $400. Cunningham pulled the cash out of his pocket and handed it to her, right on the spot. He could make that back in a day or two.

One day, on the corner, Cunningham noticed a stranger walk by slowly, peeking at Cunningham and his colleagues out of the corner of his eye. Minutes later, he walked by again. Cunningham turned to a friend. “I think he’s trying to stick us,” he said. This was common. Dealers always had to be on the lookout for rogues who would try to rob them. Cunningham tells it now: “Next thing I know, he rolls back up on us, and he’s got a two-barrel shotgun and I’m staring down both barrels. I’m thinking, This is it. This is how I’m going to die.”

But salvation arrived in the form of sirens. They screamed in the distance, growing louder every second. The stickup boy ran. Cunningham ran too. “You would think that would have scared me straight,” he says. “But where was I the next day? Right back on that corner.”

It wasn’t until that fall that Cunningham reconsidered his life’s direction. He boarded the bus for the first day of high school. He sat through his classes, met his new friends, and went home. After school, he returned to the corner.

“Where you been?” an older kid asked Cunningham.

“What do you mean, ‘Where have I been?’ At school!”

“No,” the older kid said. “No school. You gotta stay here so we can get this money.”

Here’s Cunningham, explaining it now: “I don’t know why it was that that did it. Something else should have made me realize it a lot earlier. But it was like one of those ‘eureka’ moments. It was, ‘Oh, damn, I really can’t be doing this.’” Cunningham never sold drugs again.

Years passed. Cunningham stayed in school and off the streets. Graduation approached, and Cunningham dreamed of going to college to study art. He’d loved comics as a kid and he had spent hours filling sketchbooks with his drawings. “Get your portfolio together,” his art teacher would tell him. “Make sure you’re applying to colleges.”

Cunningham never did. “I just forgot,” he says. “All of a sudden the deadline passed, and it was too late.” With graduation looming, Cunningham faced the reality of becoming a North Philly cliché. Young man, left to choose between a minimum-wage job and dealing drugs. He knew what he’d choose. Give him a few months and he’d be back on the corner.

That was, until a Navy recruiter showed up at Cunningham’s high school. The recruiter promised money for college and a chance to travel the world. He told Cunningham that foreign women loved American men in uniform. Cunningham didn’t need to hear anything more. He enlisted on the spot.

David Spagnolo

When joining the Navy, Cunningham filled out a form that asked for his hobbies. “Boxing,” he wrote. This wasn’t exactly true. Cunningham liked the idea of boxing — the notion that he could beat someone up without feeling dread or remorse. But actual boxing? He’d never really done it. As a teenager he’d gone to a gym in Philly a few times, but the trainer always told him to hit the bag. Cunningham wanted to hit people. So after a few sessions, he left and never went back. But Cunningham heard the Navy had an actual boxing team. Making that team became his biggest goal.

Soon enough Cunningham was in the ring. “Not boxing,” he says, “just fighting.” And soon after that, he was on the team. He traveled and fought and won again and again, and in between, he worked on ships stationed around the world, refueling jets. Cunningham loved the Navy. He considered making it his life’s work. But the more he fought, the more he won, and he began to realize that someday someone might pay him to box. So he left the Navy, moved to Atlanta, and started training with the dream of turning pro.

In Atlanta he met Livvy. She was smart and confident, with brown, oval eyes, and she wasn’t half-bad in the ring. So Cunningham took her to see Pitch Black, and then he took her to dinners and on walks, and then they moved in together and merged lives, routines, dreams. Livvy had a college degree and a well-paying job at Turner Broadcasting. Cunningham had a training regimen and a graveyard shift at the FedEx loading dock. After a while, he lost that job and Livvy told him not to work anymore. Just box, she said. Give it a shot and see where it goes.

For his pro debut, a four-rounder in Savannah, Georgia, in 2000, Cunningham earned $1,000. He kept fighting, and over time, the purses grew. Two thousand dollars. They moved to Virginia, then Philadelphia. Five thousand dollars. They had a son, and they named him Steve Jr. Seven thousand five hundred dollars. Livvy got pregnant again. Ten thousand dollars. They had a daughter and named her Kennedy. She had a round face, bright eyes, and a congenital heart disease.

Kennedy was born September 6, 2005, with hypoplastic left heart syndrome. Half her heart was underdeveloped and incapable of full function. After she was born, Steve and Livvy got to hold her for 10 minutes before she was taken to the ICU. So began the first year of Kennedy’s life, which she spent in the hospital. There was the surgery, the day after she was born, that went hours longer than expected, with the doctors struggling to successfully close their incisions as Kennedy nearly bled to death. There was the bypass machine that she needed for longer than anyone had hoped, and there were the fluids that built up, bloating her body and stretching her skin. There were the moments when Livvy heard doctors say, “I don’t know if she’s going to make it through the night.”

Steve spent mornings in the gym and afternoons at the hospital. Livvy’s mother came on weekends to help with Steve Jr. The Children’s Hospital of Philadelphia became a second home. They promised each other they would keep laughing and smiling. They vowed not to let fear take over their lives.

Kennedy had two surgeries that first year, one to put a stent in her heart and the other to reroute her blood. She needed one more for her heart to fully function, so that the right side would do the job of the entire organ. Only the doctors said Kennedy couldn’t handle it. She was too small, too weak. She needed time to grow and then, finally, they could operate once more.

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Years passed and Kennedy grew. She watched her dad become one of the top 10 cruiserweights in the world, and then one of the top five. She started to talk at age 3 and learned to walk a year later. She waited at home in May 2007, when her parents traveled to Poland and Livvy watched Cunningham outpoint local favorite Krzysztof Wlodarczyk to become the IBF cruiserweight champion. Kennedy enrolled in school and learned to sing and got a puppy named Kayo (pronounced “KO”). Her dad defended his belt, then lost it, and then decided, in 2012, that he was finished fighting at cruiserweight. Kennedy was 7. She still needed a third surgery. Her dad was 36. He needed a new weight class.

“People say, ‘Oh, you getting that heavyweight money,’” Cunningham explains. “Like there’s some huge difference between cruiser and heavy. It’s not like that at all.” Cruiserweights draw little attention in the United States, but in Europe, Cunningham could command a $200,000 purse to defend his championship. But after he lost his belt, the opportunities dried up. Matchmaking in boxing often boils down to the risk/reward balance presented by an opponent. Without the belt, a top cruiserweight contender like Cunningham, with no following in his home country, meant too much risk and not enough reward for European fighters. Plus, Cunningham was already in his mid-thirties by the end of his cruiserweight run, and fighting his way back up the rankings to earn a mandatory title shot could take years.

“No one wanted to fight me,” Cunningham says. If he didn’t return home as a heavyweight, he might have to retire.

So Cunningham moved up. Now, at 208 pounds, he believes himself to be the smallest heavyweight in boxing. “They’re all bigger, and they’re all stronger,” says Richardson, his trainer. “So the question is whether he can be faster and smarter.” Cunningham won his first heavyweight bout but lost his next two. Tomasz Adamek beat him in a controversial split decision that many boxing observers believe Cunningham deserved to win. In Cunningham’s next fight, he lost to 6-foot-9, 250-pound undefeated Irish Traveller Tyson Fury by seventh-round knockout after Cunningham scored a knockdown in the second round and seemed on the verge of a huge upset. Fury set up the final left hook that flattened Cunningham with a stiff forearm to the face, and Cunningham argued the punch was illegal, but the result stood. As a cruiserweight fighting mostly in Europe, Cunningham had made decent money and lost only four matches. Now, in less than a year at heavyweight, he never earned more than $70,000 for a single fight and he’d already lost twice.

Which brings us back to Cunningham’s bout against Mansour. “He was changing,” says Livvy about the way her husband viewed the sport. “The Fury fight made him start to question things. You give so much, and you risk so much, and for most boxers out there, you make peanuts. That was when he first started to question if it was really worth it.”

Weeks before the fight, the Cunninghams had talked with their doctors. Kennedy was no longer a candidate for the third surgery, they said, because her pulmonary arteries were too small and her heart had developed a leaky valve after the previous operations. The family looked for other options. Maybe she could get a heart transplant? Sure, maybe. But her physician at Children’s Hospital of Philadelphia said that a transplant would be too dangerous. Kennedy’s lung problems, dating back to when she was an infant hooked up to a bypass machine, meant that she had developed extra blood vessels in her chest. Cutting her open would put her at high risk of dying in surgery from loss of blood. “It would be irresponsible,” Cunningham remembers the doctor saying.

“Basically,” Cunningham remembers, “they advised us to take her home and make her comfortable.” The Cunninghams wanted a second opinion. But first, Steve had to fight. “I couldn’t even imagine going through that until after the fight,” says Livvy. “The stress of a fight already takes over our entire world.” So they waited. Cunningham fought. And in the fifth round, he went down.

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“Get up, Steve!”

Livvy yelled it because she already knew that he would. In fights, she feared first for her husband’s safety, then for his goals and his dreams, and then for their family’s financial stability. If he needed to stay down, she understood. But she’d seen the look in his eyes, seen that he was still there, that he still had his wits about him, and she looked to his corner and followed Richardson’s lead.

“We can win this fight!” Richardson yelled. “Get up, and let’s win this fight!”

Cunningham got up. (Mansour believed that referee Steve Smoger gave Cunningham more than 10 seconds to rise from each knockdown.) Seconds later, the bell ended the fifth round, and moments after that, Cunningham emerged from his corner transformed. He spent a minute bouncing around the ring, dodging punches and buying time, allowing himself to regain his senses and his legs. As the round wore on, Mansour kept punching air. He would lunge, and Cunningham would dodge, and then he’d stick Mansour with quick jabs and crosses. As the sixth round came to a close, the whole fight seemed to change. Mansour was getting tired. Cunningham was just coming to life.

And so it went. Cunningham survived the sixth, then the seventh, and by the eighth round, he’d assumed control of the action. Mansour’s left eye had swollen nearly shut. He lunged as Cunningham skipped around the ring, again and again, landing counters when Mansour left himself open. In the ninth round Cunningham built his lead. In the 10th he caught Mansour off-balance and scored a knockdown, enough to put the fight away on the scorecards. At the final bell, the two fighters stumbled toward each other for an emotional, wobbly embrace. It was a moment of mutual congratulation. Only one of them could win, but after 10 rounds of exhaustion and agony, at least they’d both survived.

Cunningham saluted the crowd, then kissed Mansour on his bald head. The PA announcer made it official. By unanimous decision, Cunningham had won. There would be more fights, more motivation to keep going. It wasn’t time to retire — not yet. With the bout behind them, the Cunninghams could focus on finding a second opinion on Kennedy’s transplant. One crisis had been averted. Another could be dealt with head-on.

But no one expected what came next. Moments after the fight, Mansour spoke with NBCSN’s Chris Mannix. “He was the better man tonight,” the boxer said. “He was the tougher man.” Mansour was gracious in defeat, but he didn’t stop there. “All y’all out there,” he said into the camera. “He’s having problems with his daughter. So hopefully everybody, you know, says some prayers for his daughter. And you already know how health care is, so you know, find him on Facebook and, you know, donate some money to his family and help him.”

The Cunninghams had never considered taking donations. They’d never needed them. Insurance had covered Kennedy’s health care costs — which totaled in the millions — all her life. But the next morning, Steve woke up to Facebook messages from strangers: How can we help? they asked. Where do we send the checks?

They got phone calls, letters, emails. People around the world had seen the fight. They’d seen the way Cunningham fought, the way he and Mansour embraced. They’d heard Mansour speak so lovingly of his opponent, clear-headed in his admiration for the man who’d just beaten him, even in the post-fight fog. They wanted to help Kennedy get her heart.

And soon enough the Cunninghams found themselves in need of money. They met with doctors in Pittsburgh who agreed to add Kennedy to their transplant list. But it wasn’t enough for her to make the five-hour commute from Philly. Once Kennedy hit the list, she needed to stay within a four-hour drive of Pittsburgh. A call could come at any time, day or night, with an O positive heart and a window for a transplant. They couldn’t risk being too far away.

So Livvy and Kennedy moved to Pittsburgh, with plans that Steve and the boys would soon follow. But they already owned property in Philly. And Cunningham’s earnings from boxing had dipped significantly since he moved to heavyweight. He couldn’t afford the rent on another house. That’s when they remembered the outpouring of support after the Mansour fight. Maybe we can start a fund, they thought. Maybe that was the way to finance Kennedy’s care while living within their means.

They set up a fund at heartbyfaith.com. Within hours, donations came pouring in. Friends donated. So did family and strangers. The International Boxing Federation (IBF) gave $1,000. Cunningham’s European promoter, with whom he’d had a previous falling-out, gave $5,000. Some boxers sent Steve checks but asked to remain anonymous. Every donation sent Livvy an automated email, leaving her to sit in front of her computer, tearing up at the numbers on the screen. Within two weeks, they’d received $20,000. They would reach their goal of $25,000. All that was left was for Kennedy to get her heart.

David Spagnolo

Now it’s early October in North Philly, and Cunningham walks into the gym at Rock Ministries on Kensington Avenue. Just outside, dealers and fiends exchange goods and funds under an overpass. This is one of the city’s most desperate neighborhoods, a place the Daily Beast called a “ghoulish world of addiction and prostitution” that “exists outside the law.”

It’s also where Cunningham trains. “I love it here,” he says. “You go to bigger, nicer gyms, and someone might spy on you. No one’s gonna spy on you here.” He has a fight this Saturday against 10-0 Natu Visinia. It’s a “stay-busy” match, something to keep Cunningham’s skills sharp until he finds a more established opponent and a bigger payday. But still, this is the heavyweight division, and one punch, even from a slower, less experienced boxer (as Visinia is to Cunningham), can knock a fighter out.

Richardson walks in wearing a robe and a taqiyah, the skull cap that signifies his Muslim faith. He puts on some music — first oldies, then rap — and he sends Cunningham into the ring. The fighter punches and dodges and moves. For an hour they go through drills, and then into push-ups and torturous core workouts involving a soft, fat medicine ball.

“They bigger than you,” Richardson says, referring to damn near every heavyweight in the world. “And they stronger than you. But are they faster than you? Are they smarter than you? Are they in better shape than you?” Each question is posed as a challenge. The more Cunningham sweats and grunts, the louder Richardson gets.

Between sets, Cunningham parents. His sons, 11-year-old Steve Jr. and 3-year-old Cruz, are with him in the gym. “You wanna do push-ups?” he warns anytime he sees them breaking rules. Training and punishment can be one and the same.

One more week. That’s it. One more week and the family will be back together. After Cunningham fights Visinia, he and the boys will move to Pittsburgh to join Livvy and Kennedy and wait on a call that could come at any moment. All are hoping the timing works out. Says Kennedy: “I can’t go to the hospital yet. I have to watch my daddy fight.”

She says this several days later, sitting with Livvy on the couch in their new apartment. She’s wearing a denim jacket and a side ponytail. Her clothes cover the scar that stretches down her torso, and without the small tracheotomy hole at the base of her neck, you would see no signs of the struggles she’s faced. She likes Pittsburgh. They have a yard, and their neighborhood is quiet, and for the first time in her life, Kennedy gets to be home-schooled. But they’re eager for that call and the surgery that will come with it. They know the risks. They believe they’ll be OK.

Kennedy will be ringside Saturday night, watching her father fight for her life. The bout, at Philadelphia’s 2300 Arena, is far from Pittsburgh, but the Cunninghams have a plan to charter a flight if they get the call for the transplant during the bout. Until then, she’ll pass the days with schoolwork and Nickelodeon and computer games, with occasional intermissions to sing Beyoncé songs on a home karaoke machine. At night, just before bed, she usually pulls out her iPad. She Googles her father and pulls up one of his marquee wins — Krzysztof Wlodarczyk, Marco Huck, Amir Mansour. Only Saturday, against Natu Visinia, the action will be live, the violence will be real.

“I don’t like the part where he gets knocked down,” she says. She does, however, like the part where he gets back up.

This article has been updated to correct Kennedy Cunningham’s age to 9 and to reflect that Kennedy will indeed be ringside for Steve Cunningham’s fight on Saturday in Philadelphia.