Whitney Houston songwriter on star's influence

Some of the warmest tributes to Whitney Houston have come from other artists who worked with her.

Diane Warren wrote seven songs for Houston, including "Could I Have This Kiss Forever" and "I Didn't Know My Own Strength."

Warren said the death of the star at age 48 just hasn't sunk in yet.

"I don't think I've processed it," she said. "Yesterday morning when they showed footage of the coroner, of the truck driving away, that's when I started crying, that's when it was real. It was like, 'wow.' You know what I mean? It's so surreal."

Special section, Whitney Houston: Death of a pop diva

Gayle King noted a comment made by pastor T.D. Jakes, executive producer of Houston's upcoming movie "Sparkle." Jakes said, "I did really get the sense that she was really trying to make a comeback. ... And I think that the reason that so many people are devastated is because it is not just her music, but it is her misery that attached itself to the hearts of Americans, and we watched her struggle to regain her footing after a tumultuous relationship and bouts with abuse and substance abuse."

Warren, in response to that comment, said, "A lot of great artists are troubled souls, aren't they? Musically, her legacy and her work speaks for itself. It will stand the test of time forever."

"She influenced every singer that we know, (every) modern singer has been influenced by Whitney Houston, whether it's Christina Aguilera. Celine (Dion). Mariah (Carey). They all got it from Whitney. ... Her music will live on forever."

For more with Warren on Houston's legacy, watch the video in the player above.

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