Tradition dictates that a new graduate must give a silver dollar to the first person who salutes him, according to their father, John Flaherty of Atherton, a Marine Corps veteran.
In this case, older brother Brian (Class of 2011) was saluted by younger brother Kevin (Class of 2014).
The tradition dates back to the days of the Revolutionary War, Mr. Flaherty said.
At graduation, Brian was commissioned a second lieutenant in the U.S. Marine Corps. He will report to Quantico, Virginia, for Marine Officers' Basic School followed by flight school in Pensacola, Florida.
Younger brother Kevin, who also plans to go into the Marine Corps, is currently conducting summer training on a ship in Norfolk, Virginia. Both boys graduated from Menlo School in Atherton and were members of Boy Scout Troop 206.
Brian was appointed to the U.S. Naval Academy in 2007 by Sen. Diane Feinstein.
Kevin was appointed to the Academy by Congresswoman Anna Eshoo last year.
"It's unusual to have two brothers at an academy at one time," said Mr. Flaherty.