Kirstie Alley got Kelly Preston's permission to write about John Travolta

Kirstie Alley sought the permission of John Travolta and his wife Kelly Preston before telling all about how she fell deeply in love with the "Grease" star in her new memoir.

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Alley recently called Travolta, her co-star in 1989's "Look Who's Talking," the "greatest love" of her life during an interview with newswoman Barbara Walters, saying, "Believe me, it took everything that I had, inside, outside, whatever, to not run off and marry John. And be with John for the rest of my life."

The actress, who was wed to Parker Stevenson at the time, opens up about her emotional affair with Travolta in "The Art of Men," and Alley reveals she made sure to get the movie icon and his wife's blessing before going public with her feelings.

She tells Jimmy Kimmel, "John Travolta is and has remained one of my best friends for almost 25 years. ... His wife is my best friend. ... They gave me their blessing, they said write the story. ... I think she's gonna like it. No one's read it yet."

And Alley insists her ex-husband Stevenson will not be surprised by anything he reads in the book.

She adds, "He knew about it then, I told him everything, I told him everything as we went along."

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