Two sons of former President Ronald Reagan have been engaged in a public disagreement over whether their father exhibited early signs of Alzheimer's disease while still in the White House.

Veteran CBS reporter Leslie Stahl, who saw Reagan have mental lapses in 1986, could possibly play a role in settling that feud -- or cause it to become even bigger than it already was.

In his new book, titled "My Father at 100," Ron Reagan, who's identified himself as a liberal and an atheist, wrote that in 1984, he began to "experience the nausea of a bad dream coming true" with regards to his father's mental condition.

The younger Reagan added that as early as 1986, his father had become alarmed at his growing lack of certain memories. "[He] had been alarmed to discover, while flying over the familiar canyons north of Los Angeles, that he could no longer summon their names," Reagan wrote.

After details of the book were revealed, Michael Reagan, lashed out at his brother.

"Ron, my brother, was an embarrassment to his father when he was alive and today he became an embarrassment to his mother," he wrote on Twitter.

"My brother seems to want sell out his father to sell books ... my father did not suffer from Alzheimers in the 80's," Michael Reagan added.

CBS' Leslie Stahl recalled in her 2000 book, "Reporting Live," that she was instructed not to ask then-President Reagan any questions during a 1986 meeting.

"Reagan didn't seem to know who I was. He gave me a distant look with those milky eyes and shook my hand weakly," she wrote. "Oh, my, he's gonzo, I thought. I have to go out on the lawn tonight and tell my countrymen that the president of the United States is a doddering space cadet. My heart began to hammer with the import...I was aware of the delicacy with which I would have to write my script. But I was quite sure of my diagnosis."

But President Reagan seemed to sharpen after Stahl mentioned that her husband, Aaron Latham, was a screenwriter. The president pulled Latham to the couch and began to talk about movie ideas.

Stahl "had come that close to reporting that Reagan was senile. I had every intention of telling the American people what I had observed in the Oval Office."

In a recent e-mail to Mother Jones' David Corn, Stahl explained why she never made that report.

"Because Reagan seemed to 'recover' -- I decided I could not go out on the White House lawn and tell the public what his behavior meant," she wrote. "Was it what I had assumed at first: senility? Was it an 'act' -- a way to avoid answering my questions? Was it some form of dementia (maybe not Alzheimer's)? I decided I couldn't report on my observations at all that night."

Stahl continued: "Later, when I would ask White House officials if they had ever seen him float away like that, they'd say yes, but that, as with me, he always pulled himself together. It was confusing for everyone."

"I now believe [Reagan aides and his wife Nancy] covered up his condition, and many continued to as they wrote their memoirs. But then, the public knew something wasn't right. There were all sorts of signs. We all looked the other way," she concluded in her book.

"I would have been declaring the president unfit to serve, or at least raising the possibility," Stahl told Corn.

"And such a report would have suggested a White House cover-up -- at a time when tense foreign policy matters were in the news and midterm elections were a few months off," Corn noted.

President Reagan was said to have not experienced the "tell-tale" signs of Alzheimer's until 1993, before his official diagnosis in late 1994.

-- With earlier reporting by Stephen C. Webster