'The children knew everything': Trump biographer explains the legal liability for the 'family business'

Pulitzer Prize-winning journalist Michael D'Antonio explained the legal liability for Donald Trump's children as special counsel Robert Mueller closes in on the first family.

D'Antonio, the author of the 2016 book, The Trump About Trump, joined CNN's Don Lemon to discuss former Trump fixer Michael Cohen and former National Security Advisor Michael Flynn, who are both now cooperating with investigators.

"They're talking a lot," D'Antonio noted. "And this is why I think we saw reporting today that the president is incredibly upset -- worse than he's ever been."

"It's more important to him to get over on people than to win," D'Antonio argued. "He doesn't want to win by the regular rules, he wants to win by deceiving you."

"This is the thing, this is a family business," he noted.

"People are mistaken if they imagine this is a big enterprise with thousands of employees," he explained. "When the president talks about that, he's talking about everyone from the porters in front of the hotel sweeping up cigarette butts to the chief executive's offices at these properties."

"In Trump Tower, precious few people -- maybe a few dozen -- the children knew everything because he was preparing them to take over," D'Antonio concluded.

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