By Tierney McAfee
January 04, 2018 at 04:21 PM EST
Andrew Harrer/Bloomberg via Getty Images

White House press secretary Sarah Huckabee Sanders called questions about President Trump’s mental fitness to serve “disgraceful and laughable” during Thursday’s daily press briefing.

“If he was unfit, he probably wouldn’t be sitting there,” Sanders said. “This is an incredibly strong and good leader.”

Concerns over the president’s mental health are making headlines again this week following the release of excerpts from an explosive upcoming book detailing the chaotic Trump White House.

In Fire & Fury, author Michael Wolff writes of Trump staffers: “My indelible impression of talking to them and observing them through much of the first year of his presidency, is that they all — 100 percent — came to believe he was incapable of functioning in his job.”

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In an essay for The Hollywood Reporter, Wolff also alleged that Trump has had trouble recognizing old friends, an apparent hint that the president’s memory may be fading.

Back in November, Joe Scarborough made similar claims on MSNBC’s Morning Joe, saying that people close to the president have said he has shown early signs of dementia.