In a statement, Brown's family said that Kristina is struggling for her life and is surrounded by immediate family and they are asking to honour their request for privacy during this difficult time, the BBC reported.
The 21-year-old was rushed to hospital recently after being found unconscious in a bathtub at her home in Atlanta.
Whitney was found dead in February 2012, aged 48, in a bathtub in a hotel in Los Angeles.
Photograph: Jason Merritt/Getty Images
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