In an interview with The Late Show**’s Stephen Colbert** last month, President Donald Trump’s niece Mary Trump said she is fairly certain that her uncle failed the cognitive test he kept bragging he had aced.

Mary Trump is a clinical psychologist, and the author of a damning new book about President Trump's upbringing, titled Too Much and Never Enough: How My Family Created the World's Most Dangerous Man.

Colbert asked Mary Trump to explain the purpose of such a test.

She responded that she did not use the test in her own work as a psychologist but explained that it is “a test to screen for early signs of dementia.”

“We don’t know how he did on it,” she said. “But as far as I’m concerned, his talking about it the way he’s talking about it is failing the test.”

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