Remembering Whitney Houston: Jordin Sparks Shares the Real Story Behind 'I Have Nothing' (Video)

The "Sparkle" star tells THR her favorite memory of working with the late music icon.

Just one week after what would have been Whitney Houston's 49th birthday, the late pop icon will make her final big-screen appearance in Sparkle, the film that was expected to usher in a career comeback for the singer before her untimely death in February.

The premiere marks a bittersweet moment for American Idol alum Jordin Sparks, who will make her big-screen debut with the film. Sparks told The Hollywood Reporter earlier this year that the process has been "bittersweet."

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"I got to have that experience with her, and now she's not here to see the final product," said Sparks. "But she is seeing it. She's up there watching."

Speaking with THR again at the film's junket, Sparks recalled a favorite memory of working with her idol and revealed the surprising backstory behind Houston's 1993 hit "I Have Nothing," recorded for her own film debut, The Bodyguard.

"We were walking through the house that we had rented to shoot in -- amazing house, by the way -- and I was singing 'I Have Nothing' under my breath," Sparks says. "I don't know why I was doing that, since Whitney was in the vicinity, but I happened to be singing it subconsciously."

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Sparks says she was walking up the stairs when she felt a hand on her shoulder. Houston told her, "I forgot I sang that."

"And then she went into this story of how she was feeling," Sparks continues. "She was like, 'You know, I was six months pregnant and I was so tired, and they had me walking to the studio,' and she said, 'You know what, I'm doing this once and I'm out.'

"She did three takes, and that's where that song came from," Sparks adds in awe. "So to hear that story from her, I was just like, 'I gotta step my game up in the studio, too.' Three takes and that's the song that came out of it? Incredible."

Sparkle  co-star Derek Luke, who plays Stix in the film, also recalls spending time with Houston on set. "Behind the scenes and between takes is when you saw the kid in Whitney," he tells THR.

Sparkle opens nationwide Aug. 17.