CHICAGO (AP) — Even a president needs to have a BFF or two.

Meet Chicago businessman Marty Nesbitt and hospital executive Eric Whitaker. There’s a good chance you may have seen them already.

They’re regulars at President Barack Obama’s side: tagging along when he accepted the Nobel Peace Prize in Norway, buying shave ice during the president’s Hawaii vacation, shooting hoops in Washington, climbing a lighthouse on Martha’s Vineyard off the Massachusetts coast and attending A-list White House parties.

Nesbitt and Whitaker are part of a long tradition of those who serve as first friends to the man in the Oval Office. Being a friend to the president is an important job description.

“You need somebody to talk to — or not talk to — about what’s going on,” said Paul Light, a presidential historian at New York University. “You wouldn’t want to vacation with (presidential chief of staff) Rahm Emanuel, for goodness sake.”

President Bill Clinton had his circle of friends from Arkansas. President George W. Bush leaned on buddies from Texas, notably pal Don Evans, who moved to Washington to be commerce secretary.

“It’s like when Laura is around,” Bush once said, likening Evans to the first lady. “I view him as somebody who knows me well, is not afraid to give me his opinion, has my best interest at heart.”

By all appearances, that’s the kind of relationship Obama has with Nesbitt, who runs a parking company, and Whitaker, an executive at the University of Chicago Medical Center where first lady Michelle Obama used to work.

The two men and their families joined the Obamas for their winter vacation in Hawaii, where cameras caught them sampling island treats and hitting the golf course. Back in Washington, Nesbitt and Obama turned up in black track suits to head for the basketball court at Fort McNair last fall for a private game of hoops. And that was Whitaker riding bikes with Obama and his family during the president’s vacation on Martha’s Vineyard last summer.

Nesbitt and Whitaker had seats at the table last month when the president and first lady celebrated her 46th birthday at Restaurant Nora in Washington, scored coveted invitations to the Obamas’ first state dinner and mingled on the South Lawn during the Obamas’ Fourth of July barbecue.

The Rev. Carolyn Yeldell Staley, a friend of Clinton’s since their high school days in Arkansas, fondly remembers Clinton’s assistant calling to invite her to movie nights with the president at the White House theater.

Such friendships, she said, are “the link to life that’s normal.”

Obama’s friendships with Nesbitt and Whitaker stretch back years before he rose to prominence. Stories have been written about how he and Whitaker played basketball together when they were in graduate school at Harvard and how Nesbitt, whose family lives in Obama’s South Side neighborhood, met him years ago.

“There are so many connections between the two of us, it’s kind of hard to pinpoint how we actually got to know each other,” Nesbitt told the Los Angeles Times in 2008.

Obama spoke last summer about the importance of his friendship with Nesbitt.

“Having somebody who has been there when you are down as well as when you are up is invaluable,” he told The Columbus (Ohio) Dispatch.

Discretion is a big part of a presidential friendship, Staley said.

“That’s what friends are in everyday life and nothing changes just because a person’s president,” she said.

In that spirit, although Nesbitt and Whitaker are routinely photographed in Obama’s company, both declined to comment for this story. So did the White House.

Obama aides did confirm that the two friends had flown for free on Air Force One as guests of the president on official trips, including the trip to Oslo, Norway, to accept the Nobel. The two made their own arrangements to travel to Hawaii.

Despite their best efforts to keep a low profile, Nesbitt and Whitaker do attract plenty of attention for the presence at the president’s side.

“If you read the papers, you wouldn’t know that I actually have a day job,” Whitaker said when he appeared before a sold-out crowd at the City Club of Chicago last April.

Unlike some other Chicago pals, including Valerie Jarrett and David Axelrod, who are both top advisers to the president, Obama isn’t Nesbitt’s or Whitaker’s boss.

Light said a president needs some people like that around him.

“You need somebody who doesn’t have an agenda, and that’s part of getting away from this impossible job and getting recharged,” Light said.

Staley said when she moved to Washington after Clinton was elected, she went to work as deputy director at the National Institute for Literacy, which was not a presidential appointment.

“I wanted to be able to be with him and in his company and not have him as my boss,” she said. “I wanted to keep it that friendship.”

Staley said Clinton got a boost from having his Arkansas friends around.

“He could look across a room and see some friends and just be happy at that warm glow level,” she said.