Bobbi Kristina Brown has "barely any sign of life".
The 22-year-old star was moved to hospice care last week as her "condition has continued to deteriorate" since she was found unresponsive in a bathtub at her home near Atlanta in late January and insiders say her responses are minimal.
A source told Fox411: "She barely has any signs of life, hardly any vitals.
"Security has been beefed up and even local law enforcement have been called because the families have been told that death is now imminent and they want to make sure that photographers don't get pictures of her body being removed."
Before being moved to the hospice, Bobbi was reportedly flown to Chicago on a medical plane to see specialists suggested by family friends Tyler Perry and Oprah Winfrey.
The source said: "They too confirmed what Atlanta doctors had been saying that there was no hope.
"That's when she was taken off all meds and any artificial means of support."
The trip was taken to help convince Bobbi's father Bobby Brown that he had "truly had done all he could" to help his daughter.
The source added: "It seems that he had to get a certain amount of confirmation before really letting go.
"That trip is what convinced him to allow them to take her off her meds and to 'go naturally'."
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