Joan Rivers remains in a medically-induced coma and in serious condition at Mount Sinai Hospital in New York City.

The comedienne was rushed to the hospital on Friday after suffering cardiac arrest during a procedure at a medical center and is currently on life support, according to

Rivers' daughter Melissa says she's receiving the best treatment possible and has thanked fans for the outpouring of support for her 81-year-old mother. The family says she's "resting comfortably" but the outlook is bleak, and the family will reportedly have to make a decision whether or not to keep her on life support in the coming days, according to sources.

"My mother would be so touched by the tributes and prayers that we have received from around the world," Melissa said. "Her condition remains serious ... We ask that you continue to keep her in your thoughts as we pray for her recovery."

Melissa is reportedly "in denial," according to the New York Daily News, and, "she still thinks everything is going to be OK. She is refusing to admit that a world might exist without her mother in it.

"Others that are close to Joan are starting to realize that the outcome they want is very unlikely."

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