Travis Kelce and Jason Kelce have always been close. But while the brothers share a similar love for football and family, mostly everything else about them is the complete opposite — including their wardrobes.

“They’re complete, complete opposites in every facet, personality, style, clothing, physically,” a source close to the Kelce family tells PEOPLE. “They’re like the odd couple.”

“Jason’s a Birkenstock guy and Travis is a Jordans guy,” the insider adds of the Philadelphia Eagles center, who’s most often seen in comfortable flip-flops and sweats, and the Kansas City Chiefs tight end, who’s known to be a bit of a hypebeast with his fashion-forward looks. “But at the core of it, they have similar values.”

The source explains that Jason, 36, who is the proud dad of three daughters — Wyatt Elizabeth, Elliotte Ray and Bennett Llewellyn — with wife Kylie, has always been a quiet leader.

“He’s a pretty intense guy but really lovable, likable and doesn’t care about appearance, doesn’t care about looks and isn’t trying to be cool or dress cool, just very salt of the earth,” the source reveals.

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Travis, 34, who’s dating 12-time Grammy winning superstar Taylor Swift, is the “life of the party and Mr. Personality,” the insider shares.

“When he walks into a room, you know he’s there,” the source says. “He loves music and loves going out and partying, loves fashion and likes to take risks when it comes to fashion.”

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Travis Kelce attends Michael Rubin’s MLBPA x Fanatics party at City Market Social House on July 18, 2022 in Los Angeles, California.LEON BENNETT/GETTY

In an interview with WSJ Magazine, Travis admitted to being a style-obsessed “impulse shopper” who spends at least three hours picking out an outfit for his short commute to the locker room before each game. The Chief’s player has emerged as an unexpected trendsetter thanks to his bold game-day looks, which span everything from designer tracksuits to crushed velvet cargo pants.

“I kind of just do it off of instinct,” Travis told the outlet of assembling a look from his cavernous closet, which is actually a converted bedroom and houses a collection of more than 300 sneakers alone.

Despite his well-stocked wardrobe, and the fact that he spends much of his free time scrolling fashion sites such as Ssense and Farfetch for new finds, he said he still finds himself scrambling to get dressed on game day.

“It really just goes down to the wire,” he explained. “I kind of enjoy the creative process of the panic to just throw something together.”

TIM MOSENFELDER/GETTY; CHRIS DELMAS/AFP VIA GETTY; VIVIEN KILLILEA/GETTY

Travis acknowledged that not everyone is going to be a fan of his more offbeat looks. Indeed, the KidSuper Studio printed denim set he wore after the Chiefs’ Sept. 24 matchup with the Chicago Bears was roasted on Twitter, with some saying the paint splatter design looked like “Bounty paper towels” or a painter’s work clothes.

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“Obviously, not every look is for everybody,” he said, referencing the criticism. “I’m not going to be offended if somebody says I look like a clown if I got a fun hat on and some wacky jeans. It is what it is, I’m gonna have fun with it.”

“For the most part, I do it to put a smile on somebody’s face,” he added.

The Kelce brothers are exactly 23 months apart: Jason was born on Nov. 5, 1987, and Travis arrived on Oct. 5, 1989. The two grew up in Cleveland Heights, Ohio, where their father Ed worked in steel and their mother Donna worked in banking, according to Sports Illustrated. Raising two boys so close in age wasn’t always easy, Donna revealed in an interview with FOX 4 Kansas City.

Travis and Jason Kelce pose with their arms around each other.TRAVIS KELCE/ INSTAGRAM

“It’s a lot of broken windows, a lot of, you know, crashes, a lot of fighting … and Travis was always the one that was the instigator because he wanted his brother’s attention,” she shared.

Jason echoed similar sentiments about what it was like growing up with his younger brother Travis.

“Two-year age difference, so growing up, in typical younger brother fashion, Travis found all the other ways to get the upper hand — and that was the most annoying thing ever,” Jason said in an interview with NFL Films in 2018.

Besides annoying each other, their close age gap also led to a natural competition developing between the two. “They were very, very competitive from a very early age,” Donna told FOX 4 Kansas City.

“There were a lot of fights,” she elaborated to Sports Illustrated in 2020. “There were a lot of punches thrown. It all just stemmed from somebody being better than the other one, and the other one not being able to deal with it.”

But the competitiveness between the brothers wasn’t all bad, according to Travis. “I think the competitiveness that we had growing up is very big on why we’re even in the NFL in the first place,” he told NFL Films.