Chiney Ogwumike breaks down the skills of the Antetokounmpo brothers and whether one of them will win an NBA championship. (1:24)

ALEX ANTETOKOUNMPO THOUGHT he'd had a good game. The senior forward for Dominican High School and youngest of the four basketball-playing Antetokounmpo brothers had posted 15 points, 12 rebounds and 4 assists in a 20-point victory over Mequon Homestead High School on Dec. 7.

His older brother Giannis had other ideas. The NBA's reigning MVP was fresh off his own 27-point, 11-rebound, 4-assist game in a rout of the LA Clippers on his 25th birthday. He typically darts out of Alex's high school games quickly to avoid being hounded by fans, but after this performance, he stuck around to share some blunt feedback. Afterward, Alex fired off a text to his coach, Jim Gosz.

"You'll see a different Alex," it read.

In Giannis' eyes, Alex hadn't been good enough defensively that night, and he wasn't about to let his little brother slack off on that end of the court. Not when Alex has so much to live up to.

"I'll tell you one thing, it's hard to be Alex," Giannis said. "It's hard to have three brothers get drafted. He wants to get drafted, but he's got to get better every day. There's going to be down days, there's going to be hard days, it's going to be days that he doesn't have confidence, but that's where we step in and say, 'Hey, you're going to be good, keep working hard. Keep your head up. You're going to be really good.'"

Alex can't escape the watchful eye of his superstar brother, especially not when they share the same home. The two brothers live with their mother, Veronica, along with Giannis' girlfriend, Mariah Riddlesprigger, and the couple's newborn child, Liam Charles Antetokounmpo. The baby gets his middle name from Antetokounmpo's late father, Charles, who was instrumental in establishing the work ethic that drives the brothers today.

"He put in you that 'don't-give-a-f---' mentality," Giannis said. "I feel like the toughness, I've always had it, but that 'don't-give-a-f---' mentality whether I win, lose, play good or play bad, I just go out there and chase it. Like, what's the worst that can happen?"

For the brothers, success isn't measured in wins and losses, even though Giannis, Thanasis and Kostas play for the two winningest teams in the NBA this season. Living up to their father's legacy remains the primary goal. From the oldest brother, Francis, a retired soccer player who makes his home in Greece, to Alex, a high school senior in suburban Milwaukee with the bright basketball future, that means supporting and leading one another to greater success.

"It's the biggest thing that we've got to worry about," Alex said. "If we have one goal to fulfill in life, it's that."

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GIANNIS WAS FRUSTRATED. The Bucks had just lost in overtime to the Miami Heat in their home opener on Oct. 26. He'd fouled out on a questionable charge call in overtime. Giannis had forced the overtime session with a tip-in at the fourth-quarter buzzer, but after he fouled out, the Bucks struggled to score, missing all five of their shots from the field. Khris Middleton's potential tying shot with 0.7 of a second left clanked off the rim, and while the other Bucks who weren't in the game stood along the sideline to watch Goran Dragic make the game-sealing free throws, Giannis sat on the bench and stared up at the scoreboard.

In the locker room, Giannis sat in a daze, with his size-17 right foot planted in a big, blue ice bucket. Coming off his MVP season in 2018-19, Giannis had opened this year by fouling out in back-to-back games. While the other Bucks gave Giannis space after the loss, Thanasis rolled his chair over and consoled his brother in Greek. The two brothers and teammates conversing in their native language has become a common occurrence in the Bucks' locker room.

Middleton has been with Milwaukee since Giannis came into the league in 2013, but he said he's seeing a different side of the reigning MVP this season with his brother on the roster.

"You see them talking, joking and how they treat one another," he said. "You can just tell how they were raised to be tight and close-knit."

This is the first time in Giannis Antetokounmpo's seven NBA seasons that one of his brothers has been his teammate. Ned Dishman/NBAE via Getty Images

Thanasis, Giannis, Kostas and Alex were all born in Greece after Charles and Veronica emigrated from Nigeria when Charles' professional soccer career ended. Francis, the oldest Antetokounmpo brother, stayed behind in Lagos with his grandparents and eventually followed in his father's footsteps as a pro soccer player.

The four other brothers have found success in a different sport. But before they became NBA players, Thanasis and Giannis sold CDs, DVDs, glasses and watches on the street in Greece to help supplement the family's meager income. Charles worked as a handyman, and while life wasn't easy for the family, he always tried to set a positive example for his children.

"My dad didn't have nothing," Giannis said. "He didn't have a house. He didn't have a car. No, he didn't. Not one in his name. Obviously, we were living somewhere and we were driving a car, but it wasn't his, so, man, all he had was us. We basically are his legacy."

Nearly three years after Charles' death, the brothers do everything they can to live up to the example their father set for them. They're in contact every day thanks to a lively group chat where they give one another advice about basketball and life.

"I feel like we've all come in together after my father passed away," Kostas said. "Everybody is trying to help. Obviously, my older brother Thanasis and Giannis had the biggest role to do, to step in and help more with my mom, me and Alex. But I've seen growth in Alex, and they've seen growth in me just becoming our own men."

Sometimes that support means holding one another accountable when they're not living up to the high standard they've set for themselves. Giannis is the most accomplished, but that doesn't make him immune from being called out by his older brother.

After a disappointing Game 1 loss to the Boston Celtics in last season's Eastern Conference semifinals, Giannis got a call from Thanasis, who was in the midst of a championship EuroLeague run in Greece playing for Panathinaikos. Kostas sat next to Giannis as the brothers spoke for at least an hour and a half on speakerphone. The older brother urged Giannis to "be more aggressive."

"First of all, have fun," Thanasis told Giannis. "And just understand that there's no shortcuts to nothing."

"Yeah, man, you're right," Giannis responded.

The Bucks went on to beat the Celtics in five games.

"We always speak the truth," Thanasis said. "We always keep it honest. That's how we get better. That's the most important thing."

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NURSING A COMFORTABLE fourth-quarter edge against the New York Knicks at Fiserv Forum on Dec. 2, Thanasis nailed a 15-foot fadeaway and then flashed the family's famous mean mug to the sideline, which brought Giannis to his feet on the bench. Giannis had seen that face plenty of times before, playing one-on-one against Thanasis when they were growing up.

Neither brother will go into detail on who would win those games as kids, but Giannis says he took several aspects of the game from Thanasis -- including the mean mug -- and still holds him in high regard, even as he's become the MVP and Thanasis now plays the supporting role as his teammate.

"Since we were little, he always did that," Giannis said. "When we were little, he was playing way more than me so he was mean-mugging even more. I never got better than him."

"My dad didn't have nothing. He didn't have a house. He didn't have a car. No, he didn't. Not one in his name. ... all he had was us. We basically are his legacy."

Thanasis will beg to differ.

"None of us will say we're better than each other because that's how we are and being modest and everything," Thanasis said. "But I feel like we really work hard."

They've made sure they instill that same work ethic in Alex. The family sees limitless potential in the youngest Antetokounmpo brother, who checks in at 6-foot-8 and 200 pounds at 18 years old. The older brothers do everything they can to make sure that potential doesn't go to waste.

"One thing about Giannis, there's no gray area with him," Gosz said. "He doesn't sugarcoat anything, even to Alex. He's very hard on Alex, especially when Alex is not playing up to his potential."

Alex Antetokounmpo averaged 20.1 PPG and 7.0 RPG and shot 52.1% as a senior at Dominican High School this season. AP Photo/Gregory Payan

Sometimes Giannis will show up to Alex's practices unannounced, and he stays in contact with Gosz for updates. After a game last year, Giannis noticed that Alex wasn't sprinting back on defense after plays, so he had a solution.

"I took him to the [Bucks'] practice facility around like 1 a.m. where he probably ran for hours," Giannis said. "It's not about having a good game, it's about your effort. That's what I try to show my brothers, and that's what Thanasis tried to show us. So if your effort is not there, I'll go crazy."

Thanasis, Giannis and Kostas all showed up for Alex's senior night in February before All-Star Weekend in Chicago. Alex signed the back of Giannis' custom No. 24 hoodie as he flashed a big smile. The family then made the trip to the Windy City, where they enjoyed the weekend's festivities before Team Giannis dropped an intense battle to Team LeBron, 157-155.

"After the game, my brother [Kostas] came down, and he said this has been the most fun All-Star he's been a part of," Giannis said during his postgame media session, as his family waited in a back room at Chicago's United Center. "I asked him why, and he told me, 'Because you guys were really competitive. You guys were playing to win.'"

BEFORE THE LAKERS and Bucks faced off at Fiserv Forum on Dec. 19, Giannis, Thanasis and Kostas all met on the court during pregame warm-ups. It was a rare opportunity for the three brothers to be together during the regular season.

"This is unique, we can't take this for granted," Giannis told Kostas on the court before the game. "We were three brothers under the same roof, going through the same game, going through our pregame warm-up. We're blessed and we've got to keep working hard and keep being thankful and earn more on the court."

Once the final buzzer sounded after Milwaukee's 111-104 win, the brothers swapped jerseys on the court with huge smiles on their faces. Despite claiming the NBA's best record that night, Giannis didn't bask in glory.

Instead, he dressed quickly in the locker room and darted to the arena's kids' room for a private family reunion with his girlfriend, his mother and his brothers -- almost forgetting his media obligations. Giannis wouldn't reveal what the family talked about in private, but once he emerged to meet with the media, he spoke about his humble beginnings, saying that night, "At the end of the day, I realize and my family realizes that I'm not supposed to be here."

When the Bucks and Lakers meet again Friday in Los Angeles (10:30 p.m. on ESPN and the ESPN App), the game will serve as far more than a potential NBA Finals preview. It'll be a reminder of all that these brothers have accomplished -- but it will be bittersweet without Charles there to see it.

"For some reason, I feel like he knew this was going to happen," Thanasis said of the family's NBA success. "I don't know how, but he just knew and he just always believed in his kids, and him and my mom always had hope. So my thing is that we are my father's legacy. Not what we do. We are the legacy, and Liam is Giannis' legacy, and then it goes on."