Inside Jackie Kennedy's Terror and Heartbreak Following JFK's Assassination 

Join People Perks and save up to $1,200 a year

Editor’s note: In light of the just-released documents related to John F. Kennedy’s assassination, take a look back at our 2013 cover story on the 50th anniversary of the tragedy, which features exclusive details about the first lady’s agonizing reaction to her husband’s death.

When Jackie Kennedy returned to the White House in her bloodstained Chanel suit at 4 a.m. on Nov. 23, she took the elevator up to her private quarters on the third floor.

There, she sat in her bedroom and quietly confided her deepest fears to her personal assistant, Providencia Paredes, who was always by her side.

“She was scared,” Paredes told PEOPLE in a rare interview for a cover story pegged to the 50th anniversary of the assassination in 2013. “She cried and she said, ‘I thought they might kill me too.’ ”

To the world, she was the black-veiled widow who planned her husband’s funeral and mirrored the nation’s grief, a model of dignity and grace. But to her young children, Caroline and John, she was “Mummy,” who threw John Jr. a birthday party hours after his father’s funeral, just as she had promised him a few days earlier.

“She did not want the children to think about what happened,” confides Parades. “They were so young. She did not want them to be sad.”

RELATED VIDEO: Revelations from Jackie Kennedy’s Personal Assistant

In the weeks and months that followed, Jackie moved to Georgetown and eventually, Manhattan, where she found the anonymity she craved.

Clint Hill, 81, the Secret Service agent guarding her during the Dallas motorcade, recalls the grief of the first year.

“She was sad,” says Hill, who spent the following year watching over her in New York. “She didn’t have the same radiance as before. But she grew stronger. She was already thinking about his legacy. She was always thinking ahead.”

Simon Cowell Rushed to Hospital After \'Scary\' Accident at His London Home

2 Singer, One Direction Songwriter Teddy Geiger Reveals Transition: ‘This Is Who I Have Been’

3 All the Secret Symbols, Hidden Messages and Subtle Shade in Taylor Swift’s New Video for ‘…Ready for It?\'

4 Caitlyn Jenner Flaunts Sexy Suit as She Fulfills Lifelong \'Fantasy\' of \'Walking on Beach Being My Authentic Self\'