Jennifer Hudson Breaks Down During Whitney Houston Tribute at Grammys Rehearsal

Jennifer Hudson deserves all the praise the music industry can muster today as she prepares to pay tribute to Whitney Houston, the R&B superstar who was found dead in her hotel room on Saturday afternoon, hours before she was due to make an appearance at the annual Clive Davis pre-Grammy gala. 

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Not surprisingly, Hudson is said to be "having a hard time" at rehearsal for the tribute number, which will air three-quarters of the way through the broadcast, as part of a broader "In Memoriam" segment. She is singing Houston's monster hit "I Will Always Love You."

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A Grammy crew member tells The Hollywood Reporter that Hudson was "crying and had to keep pausing" to collect herself during the Sunday afternoon rehearsal (the show kicks off at 5 p.m. PST). "She was having a hard time getting through the song, especially on the second run-through."

Chaka Khan has also been added to the tribute number with possibly more surprise guests to be announced.

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While competing on season 3 of American Idol, Hudson sang Houston's "I Have Nothing" one week before being eliminated. 

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Twitter: @shirleyhalperin