Washington (CNN) Jennifer Lopez sought marriage advice from an unlikely source as she prepares to tie the knot: the "Notorious RBG."

US Supreme Court Justice Ruth Bader Ginsburg said the global pop star called her "about a month or so ago" wanting to meet the justice and introduce her baseball legend fiancé, Alex Rodriguez. (The couple got engaged in March .) The 86-year-old dished on the meeting during an event Saturday at the Library of Congress.

The couple, Ginsburg recalled, came to her Supreme Court chambers where she said they "had a very nice visit."

"She mostly wanted to ask if I had any secret about a happy marriage," the justice said of Lopez. "But now A-Rod is traveling with her to concerts all over the world."

Ginsburg was married to her husband Marty Ginsburg for over 50 years before he died in 2010.

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