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When Kris Jenner met Bruce Jenner a few decades ago, she knew he struggled with his gender identity. She was convinced, though, that she could "fix him."

In its latest cover story, PEOPLE magazine cites multiple sources who confirm that Kris knew about Bruce's secret, but she may not have known the extent of it.

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"She knew that he struggled with gender identity," a Jenner source told the magazine. "She knew he had been on hormones and that his body had changed."

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Bruce, however, admitted that he "downplayed" how serious he was about transitioning to become a woman, even though he had 36B-sized breasts when they met (from the hormone therapy). Kris "never knew Bruce wanted to be a woman," a source said. "She thought Bruce had a little quirk and he asked her to keep it a secret, so she did."

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When it came down it, Kris simply couldn't comprehend what it all meant.

"Before Kris and Bruce got married, Kris assured his ex-wives that she knew about 'the issue,'" the Jenner insider says. "She wanted them to know that she thought it was just a phase and that she could 'fix' him."

Now, though, the secret is out and the family can breathe a sigh of relief.

"The whole family is relieved [the news is out]," the source says.