Whitney Houston and Kevin Costner on ‘The Bodyguard’ Bond

Whitney Houston's co-star from "The Bodyguard," Kevin Costner, will speak at her funeral this weekend. And that speaks to the special bond the two developed over their blockbuster movie.

The 1992 movie was a hit, and the song "I Will Always Love You," became Houston's signature anthem. The film starred Houston as a megastar threatened by a stalker, with Costner playing a Secret Service agent sent to protect her. The movie struck a note with fans, grossing $400 million worldwide. And the movie soundtrack is the most successful of all time.

A few years back, Costner told "Good Morning America" how the singer came to the role. He recounted that when he saw Houston before the movie, he thought, "She just really has it." He added it was no mystery to him how she ended up in "The Bodyguard." The actor explained, "She was such a true beauty and such a musical instrument. And I really wanted her (for the part)." So much so, he was willing to postpone the movie. He said, "There was a moment in time where it could have maybe been someone else, and I said 'I want to wait for Whitney.' Ultimately, Warner Brothers agreed to wait a year for her. "

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Costner also told the backstory of how "I Will Always Love You" came to be the song in the movie. He had planned for it to be "What Becomes of a Broken Heart." But during the year wait, that song was in another movie. Costner liked the Dolly Parton song, and eventually, despite some concerns about "this little country song," Houston sang it a capella. Safe to say that the song was a good decision.

The producers also wondered how an audience would react to a mixed-race relationship. Costner felt strongly this should not be an issue. He said, "This is not race. This was about good, old-fashioned chemistry. … I kissed her once for everybody in America, and I kissed her once for myself." All together now, "awwww."

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In a 1993 interview with Entertainment Tonight, Houston confessed she didn't think she was ready for acting, but Costner changed her mind. She said, "He made me feel so comfortable. … He was like whatever you need we will supply for you." One thing he told her not to do: take acting lessons. He told the singer, "We want you and what you bring to the character." Houston added, "I felt more insecure about the pressure to do this film."