Less than a week after receiving full custody of Michael Jackson's three kids, 79-year-old Katherine Jackson says "the children are doing fine."

She also denies rumors that her husband Joe Jackson has been banned from seeing them. "I don't know why they're saying he's not being allowed in the house," Katherine said in a telephone interview that aired on Sunday's Geraldo at Large on Fox News. "My husband's never done nothing of the sort that they trying to say he did 39 years ago. I don't understand that, and I just believe it's something that they cooked up."

See photos of Jackson and his kids through the years

Asked if Joe is a good grandfather she replied, "Of course, he is. And the children will tell you that he is."

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She also addressed accusations surrounding Dr. Conrad Murray, who reportedly gave her son Michael a lethal dose of anesthetic Propofol the night before his June 25 death at the age of 50.

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"All I know is that my son is dead, and I don't think he just died of natural causes or whatever," she said. "He's too young for that. Something happened, I don't know what it was and I can't say."

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