Joan is expected to come out of her coma as early as today, but doctors say that at this point there's no telling what sort of brain damage she may have suffered and the rehab process will almost certainly mean the end of Rivers' nearly 60-year career in comedy.
Insiders tell Radar Online that even a best-case scenario would likely involve a "years long rehab process."
Despite the dire diagnosis, sources at Mount Sinai hospital say that not only has Melissa Rivers remained strong, she's been a source of strength to other families who are camped out at the NYC hospital awaiting word on the health of their loved ones.
"She's the person who's keeping everyone together," said one source. "She is her mother's daughter and she's tough as nails."
We'll keep you posted on the state of Joan's condition as more details become available.