Sources say she has been transported to another hospital for treatment.
After Valerie Harper was rushed by ambulance to the hospital Wednesday night, a source close to the family tells ET that her family says she is now in a coma.
The 75-year-old actress was found unconscious backstage at the Ogunquit Playhouse in Maine, where she was performing in the musical, Nice Work If You Can Get It.
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The source also says that despite reports saying Harper was discharged from the hospital on Thursday, she was actually taken via med-vac to a larger hospital for further treatment.
At the time of her hospitalization, the show’s director told crowds, "She wants all of you to know after some fluids and rest, she hopes to be right back here on stage later this week." However, a source told ET at the time, "It doesn't look good."
The Mary Tyler Moore star was diagnosed with terminal brain cancer in 2013, after previously beating lung cancer in 2009. Last year, she told ET her cancer had not been "cured,” but, "In a way, it's a positive thing to know that a year's gone by and it's nowhere else in my body...I am cancer free from the neck down, so far."
ET reached out to Harper's husband and manager, Tony Cacciotti, but did not hear back.
Here's what Harper told ET about her health last we spoke to her: