"Recently, I walked into the room and I don't think she wanted to see anyone and she didn't say anything," Kate told Meredith Vieira in an interview on NBC's "Today" show on Friday.
"But I was given a very clear signal, a hand signal, that I should probably leave the room. So I did!" Kate said recalling when Farrah jokingly gave her the middle finger.
Farrah's physician, Dr. Lawrence Piro, who appeared alongside Kate via satellite from Los Angeles, said the 62-year-old TV icon is holding up well and plans to watch her documentary, "Farrah's Story," which is set to air on NBC on Friday.
"She is capable of doing that, and she plans to watch it tonight at her home with both Ryan [O'Neal, her longtime companion] and Alana [Stewart, her friend] and some other close friends," he said. "We hope she will feel up to that and she's looking very much forward to that."
Dr. Piro also recalled a recent humorous moment with Farrah.
"We had to do a little procedure yesterday and at the end of it, she turned to another doctor and myself and she said, 'You guys should have a drink now,'" he told Meredith.
"She's obviously having a lot of side effects that come with cancer and that come with cancer chemotherapy," he added. "She's weak and she's spending a lot of time in bed resting. But overall, she's in good spirits and she certainly still has her trademark sense of humor, which has helped her through all of this."
Kate addressed the multiple tabloid reports claiming her "Angels" co-star was clinging to life, saying, "[Those reports] really do hurt a human being and a person like Farrah, who has to read that she's dying and she's lost the will to live."
Dr. Piro called those tabloids reports "completely false," and noted that Farrah is "just 100 percent crystal clear and on the money and with a very sharp wit."
Kate said that Farrah hopes Friday's documentary will help other cancer patients and their families.
"This was meant to give to others hope and inspiration," Kate said. "It's made me all the more proud to call her a friend… I've learned that she's the most courageous human being I have ever known. I knew that she was brave, but I didn't know that she had the courage of the depth and magnitude that she has and she shows everyone in this documentary."
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