Coaching, especially at the high school level where it's never going to be about getting rich, requires deep reservoirs of passion and compassion and sacrifice.
The Cantrell brothers were fortunate to have grown up with two fine examples of those qualities.
Adam and Will, now both head coaches in Gwinnett County, learned early and often lessons that convinced schools to trust them to lead programs at young ages.
Adam was 23 when Providence Christian, his alma mater, hired him as its baseball coach more than a decade ago, and he's built it into a perennial state contender.
Will, now 26, was given the reins for Hebron Christian's boys basketball team earlier this summer after three years as an assistant under Ron Garren at Monroe Area.
"I was thinking a little bit ago, 'Why did I even get into coaching? Why did I want to do this?'" Will said. "It's certainly not for the money.
"I think probably the reason Adam and I do what we do is because of our dad. He made sacrifices for us, for his job, that are just amazing. Growing up, he always, always, always emphasized, 'Just do what you love. Don't worry about money or anything like that, just do what you love.'"
Because Bill Cantrell knew the opposite side of the coin.
"He did something that he didn't love," Will said. "He worked at Lockheed. He hated it, but he did it because he, on some level, felt like he needed to do that to provide for his family."
"Especially once we started going to private school," Adam said.
Instead of lamenting or complaining, Bill just encouraged his kids to take a different path. And coached both boys in sports they came to love enough make into careers.
"But his attitude, which was just an amazing example, was always that nothing is a sacrifice for me personally if it means helping my children," Will said. "That was his whole outlook on his job."
When Will, 81/2 years Adam's junior, was young and Bill's job kept him overseas for months at a time, it was Lynda Cantrell who shuttled Will -- and often his teammates -- to all AAU basketball games and travel baseball. Often in the same day.
"She was having to take me from a doubleheader in the morning over in Marietta to a game at night somewhere up in North Georgia," Will said.
"And she was cleaning houses and painting in her spare time, just to make money to keep us in school," Adam said.
Lynda's work ethic and instinctive generosity are qualities both her sons try to use as coaches.
"As much as dad sacrificed, mom did too," Adam said. "She is just so selfless. Completely full of love and mercy and demonstrating how you love on people to show them that they're important.
"And as a coach, if your kids don't feel like you care about them, you're fighting an uphill battle. She modeled that."
Will knew early he wanted to be a basketball coach, as a 9-year-old sitting in Miss Kathy Miller's class at Providence.
Adam never planned on being a high school teacher or coach. After getting his biology degree from Presbyterian, Adam enrolled in graduate courses at Georgia State with the intention of becoming a veterinarian.
"Coming out of college, I was done with baseball," Adam said. "Didn't even care if I went to a Braves game that summer."
Then Will's travel coach quit midseason.
"In the end, him and one of his buddies came and begged me to help a little bit," Adam said. "I fell in love with it in one practice. That was it."
Will laughs at that, but he's serious when he talks about Adam's coaching ability.
"I'm not trying to say that I was any good at baseball, because I wasn't very good, but I had some really good coaches in baseball," said Will, who played until he went to college. "He was the best I had."
An already evolving relationship took another turn when Adam later was hired as Providence's head coach. Will was a sophomore at the Lilburn private school then.
"When I started coaching him, it was tough because not only were we brothers, but we were friends and then I was trying to be his coach," Adam said. "So there was an interesting dynamic there. Then when I stopped coaching him, our relationship really grew. Because there was no more of the frustration of, 'Get off my back, you're my brother. Well, you're also my player.'
"But because we had gone through so many different stages, by the time he was in college, it was great."
With such a big age difference, the early years were far more contentious.
And, of course, there are two perspectives on it as well.
"First of all, it's not just 81/2 years between me and my brother," Will said. "It's 101/2 between my sister (Cayce) and I. Then we have another brother, David, who is six years older than Adam.
"There's all these different dynamics."
As a kid, Will wanted to be wherever Adam was and followed him around everywhere.
"Which he hated forever," Will said with a cheeky smile.
Adam nods emphatically, straight-faced.
Then when Adam was at Presbyterian and Will was entering his teen years, it became more of a competition.
"He'd come back from college and if he was going out with his friends to play basketball or football or whatever, I always wanted to go -- just so I could be better than him," Will said.
Once Will got into high school, a friendship began to develop. Even after Adam took over as his coach.
"From my perspective, he was a go, go, go kind of kid," Adam said. "He never sat still. Was always going. And I always have been just very bump on a log. I sit around and do my thing. And he wanted to do stuff.
"When I didn't want to, he was inventing new ways to get me involved, which was chasing him around the living room."
During Adam's high school years, he called it a love-hate relationship.
"I still loved him like crazy, but it was tough," he said. "When I went off to college, I can remember sitting him down and being like, 'OK, you're 10, you don't need to act like this anymore. If you want to spend time with me, ask me to go do this with you and I'll go do it. Don't annoy me to the point that I don't want to do anything with you.'
"And for whatever reason, it just clicked with him. There were times he came up and stayed with me in college."
They may still argue now and then, but it's more likely to be over things like the 50 greatest athletes or the drafting of college players.
Not that it can't still get intense.
"The last argument/heated discussion we got into, Cat, my wife, and (Adam's wife) Erin were in the kitchen," Will said. "I remember after like 30 minutes of just going back and forth, I was sweating and he was sweating. I walked into get something to drink and Cat's like, 'Are you OK? Do we need to leave?'"
Will and Adam both laugh heartily at that. They enjoy the idea almost as much as the arguments.
There is one point of contention, though.
"I'm disappointed he's going to Hebron instead of Providence," Adam said. "And I'm not afraid to say that, on the record. Because I've always wanted him to come and be with us.
"Being at Hebron, the opportunity he has there, it's going to be a good fit for him and he's going to be there, I hope, for a long time. Unless somehow I can scam him into coming back to Providence. But I don't really see that happening."
It won't keep Will from rooting for Adam's Providence teams though.
"If it's ever Adam's team against anybody, I'm going for Adam's team. Period," Will said. "There's not even a question. I think that's how it should be.
"If it's girls soccer or if y'all ever get football, then I'll go for my kids that I teach. But if it's ever Adam, then I'm going for Adam."
Will might have to deal with some mixed emotions if he can schedule the boys basketball team to play his alma mater Providence in the coming years. But it's a situation he looks forward to.
"Ever since I got a job coaching, Mom's always saying, you and your brother are living out your dad's dream," Will said. "I think if he could have coached, he would have done it on a more permanent basis. That's something I've always wanted -- is to get him on my staff. Some how, some way."
"Good luck," Adam said. "I've been asking him for years. I've asked him every year since he retired from Lockheed three years ago."
Will probably has an advantage in the campaign since their dad always loved basketball best.
"He had me doing fundamentals stuff from like 4 years old, like head-up dribble," Will said with a grin.
"He loves the fundamentals of the game and shooting technique and all that good stuff. So I'm going to get him somehow or another."
Adam admits his dad always was more comfortable coaching basketball.
"That's what he's always told me, 'You don't want me,'" Adam said. "So Will actually does have the better chance. But neither one of them is going to hear the end of it if he goes and helps him first."
Adam doesn't wait until then to get in a little good-natured razzing of Will, something that permeates their relationship.
"I'm going to tell Will it's because dad felt sorry for him, that he needed more help," Adam said.
"Which could be true," Will said, not rising to the bait. "Adam's a seasoned vet. If I can get my program to where Adam's gotten his, I think I'll be doing pretty dang good."