It is nearly impossible for Notre Dame men’s lacrosse goalie John Kemp to open his computer or check his cellphone and not have a message waiting for him from one of his three older brothers.

All four grew up in Potomac and went to Georgetown Prep; two older brothers were all-American goalies in college.

There will be two certain topics of conversation among the brothers this week: The fourth-seeded Fighting Irish (13-2) face No. 1 Loyola (16-1) in an NCAA men’s lacrosse semifinal on Saturday at 2:30 p.m. at Gillette Stadium in Foxborough, Mass.

And on Thursday, John Kemp was named a first-team all-American. The honor comes in a year in which Kemp, a junior, leads the nation in goals against average (6.23) and save percentage (.636).

Kemp’s high school coach described him as “unflappable,” and his teammates at Notre Dame noticed that trait in his first college start. Playing for injured starter Scott Rodgers in 2010, Kemp gave up four goals in less than eight minutes in a first-half stretch against Villanova.

“I was getting pretty rattled and upset watching it,” said senior Colt Power, a backup goalie and Kemp’s roommate for away games. “I was expecting him to be somewhat rattled, too. He came over to the sideline during a timeout. He got in the huddle and said, ‘If I get a groundball, I’m running down and scoring a goal.’

“I don’t know how that was going through his head. But that’s his mind-set. He’s always looking forward.”

Said Notre Dame midfielder Pat Cotter, like Kemp a Georgetown Prep graduate: “He absolutely doesn’t dwell on it when he gives up a goal. He just gets past it. He’s always really calm.”

Kemp became a strong goalie in part through working with his older brothers. C.J. Kemp was a two-time honorable mention all-American at Fairfield in 2002 and ’03. Joey Kemp was a first-team all-American at Notre Dame in 2008 and an honorable mention in 2006 and ’07.

The oldest brother, Rob, arrived at Providence to play baseball the year it discontinued the program, though he remained in school there.

In particular, the comparisons between John and Joey are easily made: Both played for Notre Dame and wore jersey No. 1.

“I get the question a lot: Who’s better, Joey or John?” Georgetown Prep Coach Kevin Giblin said. “I always say they’re different goalies. Joey had a flair for making the dynamic saves. John makes the dynamic saves look easy. But John will be the first to tell you he had some good teachers.”

John Kemp carved his own path, too. In an effort to improve his hand-eye coordination, he taught himself to juggle tennis balls in high school. To improve his foot speed, he jumped rope. And to improve both at the same time, he played hours of tennis.

Yet his brothers remain ever-present as teachers to dispense encouragement and tough love. One of the first text messages C.J. Kemp sent his brother after Notre Dame’s 12-10 victory over defending national champion Virginia in the NCAA quarterfinals last Sunday began, “I’ve re-watched the game . . .

“Sometimes in class he will turn on his computer and there will be an e-mail waiting for him from one of his brothers,” Power said.

The relationship is far from a one-way street.

Bob Kemp, their father, recalled a conversation between John Kemp and Notre Dame Coach Kevin Corrigan soon after his youngest son committed to play there.

“Kevin asked him if he wanted to save jersey number one for John,” their father said. “It had been Joey’s jersey but there was a year between Joey graduating and John coming in.

“John thought about it for a minute. . . . Then he said: ‘Please save number one for me. If I can follow in my brother’s footsteps, it would be great.’ ”