WATCH: Katrina Pierson claims to know mind of dead Ronald Reagan more than his own son

Donald Trump's spokeswoman told CNN host Wolf Blitzer she doesn't believe a tweet by Ronald Reagan's son that the iconic GOP president would not vote for Trump.

The younger Reagan tweeted on Monday night that "This most likely would be the 1st time if my father was alive that he would not support the nominee of the GOP."

Trump's spokeswoman, Katrina Pierson, was responding to Blitzer's questioning about Trump's decision to attack a federal judge with Mexican heritage and say he is biased against Trump because of his race and thus shouldn't oversee cases regarding Trump U.

"That must be a very particularly painful rebuke for Donald Trump given his admiration for Ronald Reagan," Blitzer said.

Pierson denied that it was.

"No, I don't think so at all. everyone can try to assume what somebody else would do, but you simply can't do that," Pierson responded. "I think it's unfortunate that he would go far to assume that because he doesn't know what Ronald Reagan would do because, in fact, I think Ronald Reagan would probably support Mr. Trump, considering how he has been a Republican who has been out there who has broadened the Republican base and broadened new voters and won in states that Republicans don't usually win and doing very well. The people have spoken. Mr. Trump has broken the record in Republican party turnout and I believe Ronald Reagan would support his nominee."

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