The breakout star of Super Bowl week will not play on Sunday. Donna Kelce will instead watch from the commissioner’s box at State Farm Stadium as her sons, Jason and Travis, become the first brothers ever to compete against one another in the NFL’s title game.

“It’s going to be the best day ever,” she told them on their podcast, New Heights. “Except for when you were born, when both you guys were born, it can’t get any better.”

The episode was released on Saturday, two days before she surprised them at Super Bowl Opening Night, the hybrid press conference-jamboree that kicks this week off every year. Jason and Travis were being interviewed in front of thousands of fans on a main stage at the Footprint Center when Donna emerged to hand them each a plastic container full of homemade chocolate chip cookies.

Since then she has been everywhere, giving TV interviews and even popping up at NFL commissioner Roger Goodell’s press conference to ask when he was going to appear on New Heights, always while wearing one of her custom half-and-half tops that combine the colours of Jason’s Philadelphia Eagles with Travis’s Kansas City Chiefs. A petition to have her make the ceremonial coin toss on Sunday attracted more than 180,000 signatures.

Donna has resisted that idea, saying she does not want to be a distraction. Her sons insist she could never be. They will always be her kids, but Jason and Travis are hardly young naïfs on this stage. Each of them has won a Super Bowl before, and each is as a respected leader on their team.

Jason, the older brother, is a five-time All-Pro center who has started for the Eagles ever since he was drafted back in 2011. Travis, two years his junior, is a tight end with seven consecutive 1,000-yard receiving seasons, making a case to be remembered as the best ever to play at his position.

Neither might be here without the other. Their childhood, as they tell it, was one of constant competition, whether that was wrestling and throwing lacrosse balls across the living room or going one-on-one on the basketball court. There are stories about the time Jason power-bombed Travis so hard into the sofa that it went through the hardwood floor, and when Travis threw Jason down so violently in the kitchen that the stove came off its hinges.

At Opening Night, Travis described it as “enjoyable chaos”, recalling “a lot of fun, a lot of broken windows, a lot of shattered things around the house that my parents had to deal with.” Donna, in her appearance on the podcast, said the only thing they never smashed was the TV.

The two boys would grow up to play football together at the University of Cincinnati. Jason was a walk-on running back who coaches converted to play on the offensive line. His work ethic and increasingly dominant performances helped persuade coaches to offer Travis a scholarship two years later. The younger Kelce was a more eye-catching athlete: taller with rare fluidity to his movements, but also needed to be converted from quarterback to tight end.

When Travis was suspended by the team after testing positive for marijuana in 2010, Jason moved him into his own bedroom to keep an eye on him and make sure he got back on track. He kept his brother motivated with one-on-one workouts and vouched for him with coaches, persuading them to reinstate Travis the following year.

“I wasn’t paying rent, he was helping me with food, so I was literally living off him for quite a while down there and he was my lifeline,” said Travis this week. “I was trying to do the right things, and he went into the coaches’ office and talked to numerous coaches and numerous people in the Cincinnati staff to try to get me another chance to be on the team.

“I’m forever in debt to this guy for putting his name, our name, putting his honor on the line to get me another chance. When I say I owe it all to him, I really do.”

Donna Kelce has been the center of attention throughout Super Bowl week. Photograph: Peter Casey/Getty Images

Even the shirt Travis wears for Kansas City, No 87, was chosen as a nod to his brother’s year of birth. Yet it has been hard to maintain the closeness they once had since turning pro. NFL seasons are busy, and there are a thousand miles between Philadelphia and Kansas City. The motivation to start the New Heights podcast last August came in part from wanting an excuse to speak to each other more.

“What this did was gave us a scheduled two-to-three-hour window where we have to talk to each other and we have to talk about what we’re going through, throughout the week and throughout the games,” said Travis on Opening Night. “It’s almost been like therapy, man. It’s been cool to hear what he’s going through and just to have some fun with my brother like we did back in the day.”

They were anxious, at first, about how the show might be received if they or their teams had poor seasons. Instead, the opposite has come to pass. There were New Heights off the field, as the podcast went to the top of the US sports podcast charts, and on it as they set up this appointment with one another at Super Bowl LVII.

There has been much talk of their differences in Phoenix this week, Jason the more reserved, pensive character and Travis the flamboyant showman, imitating the Rock and calling the mayor of Cincinnati a “jabroni” after the AFC title game. Donna reminded reporters that Jason, too, can be a showman, dressing up in a Mummers outfit to deliver a memorable speech at the Eagles’ Super Bowl celebration five years ago.

Chiefs head coach Andy Reid knows both players well. He was still in charge of the Eagles when they drafted Jason in 2011, working with him for two years before moving to Kansas City. He got to know Travis in that time, too, and it was that first-hand connection that led to the Chiefs selecting the younger Kelce in the third round in 2013.

“They’re both, at heart, very competitive and compassionate,” said Reid this week. “They care about people, and they care about their game, their trade.”

That they care about each other has been evident all week, just as it is on the podcast where they discuss everything from childhood to the aliens that Travis insists are living on earth right now, “either underwater or on Antarctica”. And they care about their parents too, not just Donna with her cookies and half-and-half shirts but also their more understated father, Ed.

During his appearance on New Heights, Jason and Travis goaded him with questions about who he would cheer for most this Sunday. Ed refused to pick but said he would probably go to the loser at the end since “somebody’s going to feel pretty crummy. And I want to be with them initially.”

Travis teased that, whatever happens, both parents will be losers at the end of the night, since one of their sons will be sad. “No,” insisted Ed. “One of you guys are gonna lose. I have already won, dude. I’m on the most popular podcast in sports with my sons. I have already fucking won. All the rest of this is just window dressing.”