Carolyn Bessette-Kennedy Was ‘Irked’ JFK Jr. Never Introduced Her to Mom Jackie; New Book Says It Was One of His Regrets

A new biography of Carolyn Bessette-Kennedy reveals a sore spot between her and husband John F. Kennedy Jr.

The book, Once Upon A Time: The Captivating Life of Carolyn Bessette-Kennedy, out this month from Gallery Books, reveals new details about the couple’s relationship, including a story that Carolyn was upset that John never introduced her to his mother, Jackie Kennedy, before her death on May 19, 1994.

According to the biography, excerpted in this week’s issue of PEOPLE, Bessette-Kennedy and John began dating, on and off, in the early '90s. For some of that time, John was still seen publicly with girlfriend Daryl Hannah, with whom he broke up in 1994.

Bessette-Kennedy wasn't pleased about the overlap, nor about the fact that she was not able to meet the former First Lady.

"Carolyn became increasingly irked that he wouldn't introduce her to his mother," writes author Elizabeth Beller. "'I took him to meet my mom,’ Carolyn told a friend."

Speaking with PEOPLE for a story in this week's issue, Beller says that John, at the time, may have been preoccupied with launching his political magazine George.

“I think it was hard for him to take anything other than his work too seriously at that moment,” Beller says. “If Carolyn met Jackie, I think he knew that that would sort of become a life of its own. And maybe he wasn't quite ready for that.”

“I know that he did regret it,” Beller continues. “That's one of the things that he said to several friends, one of his main regrets was not introducing the two of them.”

For more on Carolyn Bessette-Kennedy and her relationship with JFK Jr., pick up the latest issue of PEOPLE, on newsstands Friday, or subscribe here.

The relationship had its ups and downs before the couple married in a secret wedding in 1996. “The on, off-ness of their relationship between '92 and '94, partially, was sometimes off because [Bessette-Kennedy] would break up with him over the fact that he wasn't introducing her to Jackie,” Beller says. “[She was] thinking, ‘This can't be serious if he's not really introducing me to his mother.’”

“Carolyn wasn't going to put up with anything like that,” Beller continues. “One has to protect oneself."

Beller notes, however, that Bessette-Kennedy’s wish to have met Jackie may have had something to do with her own family. Her parents, William and Anne Marie Bessette, divorced when she was young. Says Beller, "I think for her, not being introduced to a parent was a particular vulnerable spot as someone who felt like maybe a parent hadn't stayed in her life as much as she would've liked when she was growing up.”

Beller’s biography explores Bessette-Kennedy and John’s complicated relationship, as well as their tragic end. The couple, along with Bessette-Kennedy’s sister, Lauren, died in a plane crash off of Martha’s Vineyard on July 16, 1999. John was 38, Lauren was 34 and Carolyn was 33.

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Once Upon a Time: The Captivating Life of Carolyn Bessette-Kennedy is on sale May 21 and available for preorder now, wherever books are sold.