Philadelphia Eagles receiver DeAndre Carter has a story to tell. And he's not alone.

In the summer of 2013, his younger brother, Kaylan, went into cardiac arrest during a weightlifting session and fell into a coma. Kaylan, 17, was entering his senior season with the Enoch Eagles in Modesto, California. He was a standout running back and defensive back and aspired to play ball both in college and the NFL. But he had an undetected disease called hypertrophic cardiomyopathy, which can make it more difficult for the heart to pump blood.

He remained in a coma for two months before he died.

On his deathbed, DeAndre made a promise to his little brother and best friend that he would make it in the NFL in his honor.

"It was both of our dreams to play in the NFL and have successful careers," he said. "I felt like I had a duty to do everything that he wanted to do that he never got an opportunity to."

5 years ago today...Love you and I miss you kid. Let's ride baby boy #KC5 🙏🏾 pic.twitter.com/wc9KIzf1No

— DeAndre Carter (@DCarter_2) August 16, 2018

It's why Carter keeps getting off the mat. He's lost track of how many times he's been cut since joining the league as a 5-foot-8 undrafted free agent out of Sacramento State in 2015. Five? Six?

Six is the answer. First by the Baltimore Ravens, then the Oakland Raiders, and twice by the New England Patriots and San Francisco 49ers. In late July, he was signed by the Eagles. The move seemed simply to be a matter of adding camp depth, but Carter has been making noise, and after a four-catch, 73-yard performance against the Cleveland Browns in the third preseason game, buzz has picked up about him possibly making the 53-man roster.

While you'll find few stories as dramatic as Carter's, there are compelling ones inside the temporary locker stalls across the league that often go untold. NFL fringe players enter and exit en masse. Rosters balloon to 90 for training camp and release to 53 before the start of the regular season. With so much attention on the 1 percent, most players work in relative obscurity during their brief stays.

Teams need to cut 40 percent of their roster by 4 p.m. ET Saturday.

"It's without a doubt the worst day of this job," Eagles defensive coordinator Jim Schwartz said. "To see guys that work as hard as everybody else, that literally don't get on that bus. You certainly feel for those guys, but at the same time you're also appreciative for what they've done and know that they've played some role in the team."

Wide receiver Anthony Mahoungou is from Paris, France. He worked as a waiter to earn enough money so he could come to the United States and attend West Hills Community College in California. He later transferred to Purdue and played three seasons for the Boilermakers, catching 40 balls for 688 yards with eight touchdowns in 2017 while garnering a spot on the Big Ten All-Academic Team. His 17.2 yards per reception ranked second in the Big Ten last season. He was signed by the Eagles in May.

“I’m from France so when people say 'Ball is life,' well to me it’s a different meaning because I literally left my family in France," he said. "Because of the different time zones I cannot call my parents, my family, whenever I want. They don’t really understand what I’m living right now. My mom, she doesn’t know anything about football. She just understands when I score a touchdown. My dad, he understands. My brother, he played football so he has a complete understanding. But I don’t think they really understand. They’re proud of me but they don’t understand how it is to be in the league, so the support that most of the guys have, mine is kind of different."

Mahoungou views himself as part optimist, part realist and very much believes in willing things into existence. He said it would be "like a miracle" if he made it on the 53-man roster of the Super Bowl champion Eagles, especially without getting much of a run in the first three preseason games.

"I believe I’m going to stick in the league. I don’t know if it’s going to be here, if it’s going to be 53-man or practice squad or anything like that. I just truly believe that after Thursday night [the preseason finale against the New York Jets] that I’m going to open some eyes," he said.

Mahoungou won't get a chance to play in that last preseason game. He was released by the Eagles on Monday, and has not yet been picked up by another team.

Cornerback D.J. Killings is trying to shake life on the bubble. He was signed by the Patriots as an undrafted free agent last May but was waived/injured right before the start of the season. It worked out all right, because he was signed to Philly's practice squad in October and watched his new team beat his old team in Super Bowl LII.

Schwartz mentioned him as one of the players competing for the slot cornerback job this summer, and he did get a couple looks with the first team, but it seems like that job is either going to Sidney Jones or rookie Avonte Maddox for now. Killings is right on the roster fringe.

When in this position, players know better than to get comfortable. Teams will put them up in a hotel for a week or two. After that, they search out housing that offers month-to-month rent. Their families typically don't move with them unless some stability is secured.

"You’ve got some long-term guys, guys that have those contracts, that have these nice houses and their whole families are up here. You’ll see that, you’ll want that," Killings said, "but you know that ain’t the right move to do right now.”

Killings compared the feeling of moving from one team to another to being the new kid at school. The uncertainty, along with the constant fight for limited reps, can wear a person down. For some, it becomes too much.

"Around this time, they just give up," Killings said. "And as soon as they give up on themselves, people can see that, so nobody would really take a shot on them. Once you get to that point, the confidence goes down in your game, you start just not caring, your competitive edge leaves. I’ve seen a lot of guys, they go through this part of training camp to where the starters are getting ready for Week 1 and the guys fighting for a spot are getting ready for that fourth preseason game and they just give up on everything.

"Next thing you know, you just hear, 'Oh, what are they doing back home?’ 'Nothing.’ If they’re from those areas back home, they’re in the streets. Or a lot of them just working a regular job. Some guys, they just can’t handle it. They just can’t deal with it.”

And some, like Carter, just keep bouncing back. Despite his efforts over the last three years, he has never played in an NFL game or even made a 53-man roster. Thursday's game against the Jets could help decide if he'll finally break through. The key to keeping after it, he said, is doing it for something bigger than yourself.

"When you hit that wall, when you hit that adversity, that rough spot, you doing it for yourself won’t always get you through that," he said. "But if you have other people depending on you or you’ve got people looking up to you, whether that’s kids, youth, in my case I made a promise to my little brother, it gives you that extra push.”

And it's that push, Schwartz said, that can be the difference in making a dream fulfilled last.

"People don't make teams for a lot of different reasons," he said. "Whether it's not a good scheme fit, maybe a numbers position or maybe an injury. It's very rare that a guy just flat out isn't talented enough. I mean, that certainly happens, but perseverance is a big thing."

"All these guys are here for a reason. All of them are here on their own merit. All of them have ability, that in the right circumstances and with enough perseverance and maybe being fortunate a little bit here and there, they can all get some traction."