D.J. Killings still has a lot of work to do, his brother Marquis knows, to convince Bill Belichick and the Patriots coaching staff he’s worthy of making the team. The cornerback, an undrafted free agent, has merely participated in rookie camp thus far.

But given all his family has endured, that small step in D.J.’s football journey serves as a huge boost for the Killings family.

Because once you know D.J.’s story, which includes losing two brothers to murder while he was in college, you might have a better sense of how meaningful an NFL job would mean to this kid.

“It’s the best opportunity of our life, of his life. It’s fulfilled his dream, and to show us, coming from what we came from, the bad things we had happen to our family, finally, there’s some good,” Marquis said of D.J., who signed with the Patriots after not being selected in last month’s NFL draft. “It’s just a blessing. Everyone’s proud of him. It’s God’s will. I feel like I made it. He made it. That’s what having a shot with the Patriots feels like for us.”

Killings grew up with six brothers. They were all passionate about playing football. Growing up in South Florida, they spent their days in the sandlots in Miami. They shared a dream of making it to the pros, and D.J. was right on course.

The Killings boys were excited when D.J. got to college to play for Central Florida, a Division 1 school. Then fate cruelly intervened.

Older brothers Fred and Reggie were both murdered. They were killed two years apart, viciously gunned down in Miami. Fred died during D.J.’s freshman year in 2013. Then Reggie was shot in front of his home in 2015 during D.J.’s junior year.

His late brothers were “idols” to D.J., his brother Aaron said. Their deaths turned his world upside down and left him devastated.

How did he deal with it?

“It was hard for him. Football and school got him through it,” Marquis said. “But he knew he couldn’t give up. (Playing football) was (Fred and Reggie’s) dream. He could make them happy by fulfilling his dream, but also fulfilling their dream. It’s just like, they’re all together. Once he’s on the field, it’s like, they’re living through him. So he couldn’t give up.”

‘Football was our passion’

D.J.’s father, Fred Killings, was a running back at Howard University who went on to earn a spot in the school’s Hall of Fame. He was later the boys’ Pop Warner coach. Yet the Patriots rookie still learned a lot about the game from his older brothers.

“My dad always had us working out in the stadium,” said Marquis, “but (D.J.) learned from seeing Fred, Reggie and Aaron playing. Football was our passion. Our light. That’s what banded us together.”

Then that band of football brothers was torn apart through two separate tragedies. Still, D.J. dealt with the grief and came out of it with a chance to play the game at its highest level.

“How he managed to get through it, I can’t even tell you. Our whole younger life was about football. It was embedded in us. School and football,” said Aaron. “But I definitely feel like he’s carrying the torch. He and (his late brother Fred) play the same position. He taught him everything he knows.”

D.J. struggled his junior year in the aftermath of Reggie’s death. But he managed to come on strong his senior year, particularly over the final six games. He played well enough to draw the attention of the Patriots and some other teams. After going undrafted, he was a highly sought rookie free agent.

The Patriots gave him $20,000 in guaranteed money and an $11,000 signing bonus, which were among the highest doled out to any undrafted free agent around the NFL this year.

Finding motivation from loss

Killings certainly has a lot of football qualities the Patriots want in their players. He is a wizard in the film room, for one. He’s smart as a whip, having graduated in three years. The 5-foot-10, 187-pound corner, a two-year starter, also ran a 4.48 40-yard dash, and had a 371⁄2-inch vertical leap at his pro day, which the Patriots attended.

It’s hard to ignore, however, the manner in which he’s dealt with his grief. Given how well the Patriots handle adversity, that had to impress as well.

Killings told the Orlando Sentinel last year that he used his brother’s deaths as fuel to continue pursuing his dream of playing in the NFL.

“They were the ones who stayed on me, they were the ones who kept my drive going,” he told the paper of his late brothers. “They were the ones who when I first got to college said, ‘It’s your time.’ I’m the second to youngest and they messed up their chances to go to college and make it to the league, but they just kept me out of trouble and kept me going.

“It was a big impact to lose them.”

The Herald requested to speak with Killings, but the Patriots did not provide access to him.

Marquis said that D.J. also relied on his faith to get him through. During his senior season, before every game, he’d tuck a small slip of paper with a different Bible scripture inside his cleat.

“That’s a big part of his motivation. It goes back to his grandmother . . . Philippians 4:13,” said Marquis. “It’s his model, his mode to live by. All things are possible through Christ. If you have faith, you’ll make it through.”

Odds are long to make team

When it comes to the Patriots, you have to be pretty special to make it as an undrafted player. If more than one undrafted player per season makes the roster, it’s an upset.

Malcolm Butler, of course, went undrafted in 2014 and by the end of the season was a Super Bowl hero. He’s the poster boy for what can happen. But Killings faces an uphill climb to win a roster spot in the regular season.

Travis Fisher, Killings’ position coach at Central Florida, believes he has what it takes to play in the NFL, particularly from a Patriots perspective.

“D.J. is a very smart corner. He’s a film rat, always watching film. He’s very smart. He has a very high IQ. He knows the game,” Fisher said. “He’s a no-nonsense type of guy. He’s never in trouble. He’s always on time. He’s always early to meetings. He’s always prepared. He’s really detailed in his film study.”

On the field?

“He’s like having a coach on the field,” Fisher said of the 21-year-old. “He did a good job for us last year, getting our defense lined up. Sometimes if we made the wrong call, he’d (correct it).”

During his four years at Central Florida, Killings had five interceptions, 22 passes defended, eight tackles for loss, one sack and one forced fumble. Killings has the versatility to line up on the outside, in the slot, or even at free safety. Fisher believes his best usage at the NFL level will be in the slot.

“I see him inside. I played in the NFL for a long time. I know what those players look like,” said Fisher. “I think D.J., his last six games in particular, were lights out.”

His late brother Fred left behind two young sons who also love football. Now D.J., competing in his first NFL camp, has become a role model to them for what’s possible.

D.J.’s father, meanwhile, couldn’t be happier at how far his son has come. He may have coached D.J. along the way, but he knows what Fred and Reggie meant to his son.

“I’m such a proud dad. I was so ecstatic (the Patriots signed him). Every kid wants to be drafted. But he’s going to a winning organization,” said Fred Killings. “The Patriots were his last workout. I was ecstatic. You’re going to learn the Patriots way. I spoke with him after rookie camp, and he said, ‘Dad, I understand why the Patriots are successful.’”

So now, dad is just patiently waiting for the right time to come to Foxboro to see his son.

“My bag is packed, I’m just waiting for the signal,” he said. “But a lot of it for me, is because I just want to see him smile because of the things he’s been through. That’s all I want to see. I want to see him smile.

“If what he’s doing with the Patriots makes him smile, I’m with it. If he told me, ‘Daddy, I got to go to Timbuktu,’ I would be on a plane to Timbuktu just to see him smile. With everything incorporated into what he’s gone through, this is beautiful. It’s a beautiful thing.”