"This is his worst nightmare," a family source told PEOPLE. "Losing Whitney [Houston] was hard, but this is a million times worse, and to lose her in the same way would devastate him."
The family source said the only child of Brown and Houston has not regained consciousness since she was found in her bathtub Saturday inside her Roswell, Georgia, home. The 21 year old remains on a respirator, with very little brain activity, the source told PEOPLE.
It's believed she was without oxygen for an undetermined amount of time.
The family source added that doctors say that a recovery is technically possible, but if it happens, it'll be a miracle.
At this moment, the Houstons and the Browns have come together for Bobbi Kristina. "Everyone is holding hands, praying, hoping for the best. Everyone knows where things are at."
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