Kevin Costner on Bobbi Kristina Brown: 'I Can't Imagine' What Her Family Is Going Through

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Nearly three years after Kevin Costner delivered a touching speech at the funeral of Whitney Houston, his costar from 1992's The Bodyguard, Costner has learned with the rest of the world that Houston's daughter Bobbi Kristina Brown is facing a life-or-death battle amid circumstances tragically similar to those that ended her mother's life.

"I was sad, obviously," Costner told PEOPLE about hearing the news that Brown, like her mother, was found unconscious in a tub on Saturday. "That family's under a lot of stress right now, just an enormous amount of stress."

After Nick Gordon discovered Brown, 21, and performed CPR until police arrived, she was immediately rushed to a hospital in Georgia. She is now surrounded by family and fighting for her life as sources say it will take a miracle for her to recover.

"I can't imagine," added Costner, 60, shaking his head with disbelief, before receiving a career achievement award at the 14th Annual AARP Movies for Grownups in Los Angeles on Monday.

Though Costner, currently starring in Black or White, admitted he hasn't spoken to Brown in "a little while," he wants nothing more than a speedy recovery for his former leading lady's daughter.

"I really hope she's okay," he said solemnly.

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• Kevin Costner on Bobbi Kristina Brown: 'I Can't Imagine' What Her Family Is Going Through

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• Bobbi Kristina Brown Is Still Unresponsive, According to Source

• Do Bobbi Kristina Browns's Social Media Accounts Hold Clues About Why She Was Found Unresponsive?

• Bobbi Kristina Brown: Inside the Troubled Life of Whitney Houston's Daughter

• Bobbi Kristina Brown Hospitalized After Being Found Unresponsive in Tub

• Stars Rally Around Bobbi Kristina Brown

• Bobbi Kristina's Husband Is Not the Bad Guy, Says Source

• Bobby Brown 'Inconsolable' Over Bobbi Kristina's Hospitalization

• Bobbi Kristina Brown Recovery Would Be a Miracle, Says Source

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