The Heartbreaking Story Behind 3-Year-Old JFK Jr.’s Moving Salute to His Father’s Casket (Exclusive)

A young John Jr. saluted his father in "the most poignant picture of the century" the same day as his third birthday

<p>Anne Marie Fox; AP/REX/Shutterstock</p> JFK Jr. (left) and at age 3 when he saluted his father

Anne Marie Fox; AP/REX/Shutterstock

JFK Jr. (left) and at age 3 when he saluted his father's casket in 1963.

When John F. Kennedy Jr. saluted his father’s coffin on Nov. 25, 1963, Phillip Hannan, the auxiliary bishop of the Archdiocese of Washington, had a front-row seat to history.

“I was standing by him,” Hannan told historian William Manchester. “I saw the reaction of the people across the street. It was an instantaneous reaction. They broke down. I had heard Mrs. Kennedy say ‘John, salute.’  I knew then that this was the probably the most poignant picture of the century.”

The funeral was held on the same day as John’s third birthday, and later that day, there was a small party upstairs at the White House.

<p>Estate of Stanley Tretick LLC/Corbis via Getty</p> A young John Jr. and his father, President John F. Kennedy.

Estate of Stanley Tretick LLC/Corbis via Getty

A young John Jr. and his father, President John F. Kennedy.

Related: Were JFK Jr. and Carolyn Bessette-Kennedy Separated When They Died? The Truth About Their Rocky Final Days (Exclusive)

“They had just laid his father to rest, saddest day in the world, and now they’re supposed to have a birthday celebration,” Secret Service Agent Clint Hill shares in a new book, JFK JR.: An Intimate Oral Biography, by PEOPLE editor-at-large Liz McNeil and RoseMarie Terenzio, John’s assistant and close friend.

For more on John F. Kennedy Jr., pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.

<p>Robert L. Knudsen</p> JFK Jr. on his third birthday, the same day as his father's funeral.

Robert L. Knudsen

JFK Jr. on his third birthday, the same day as his father's funeral.

Twenty-five years after John’s death at 38 on July 16, 1999, when the plane he was piloting crashed off of Martha’s Vineyard, also killing his wife, Carolyn Bessette-Kennedy, 33, and her sister, Lauren, 34, the new book, reveals never-before-told stories about the impact of his father’s death and John's quest to define himself apart from his famous family.

Related: JFK Jr.’s Shocking Plane Crash Death at 38: What Really Happened When the Plane Went Down (Exclusive)

One of his closest friends, Sasha Chermayeff, shares a memory of walking through the East Village with John and her son Phineas, then three years old, not long before John’s death. Recalls Chermayeff, “I said, ‘You were this age when your father was killed, exactly this age,’ and he said, ‘You never get over it.’”

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“Why did he tell me you never get over it when we were talking about his dad’s death?” reflects Chermayeff. “Because he hadn’t.”

JFK Jr.: An Intimate Oral Biography by RoseMarie Terenzio and Liz McNeil comes out July 16 and is available for preorder now, wherever books are sold.

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