(CNN) In the heat of the 2016 presidential primary fight, then-candidate Donald Trump suggested that Ted Cruz's father might have been involved in the assassination of John F. Kennedy.

"His father was with Lee Harvey Oswald prior to Oswald's being -- you know, shot," Trump said of Cruz on Fox News Channel in May 2016. "I mean, the whole thing is ridiculous."

Trump's "evidence"? A grainy black-and-white picture of JFK assassin Lee Harvey Oswald in Cuba, with a man who Trump believed to be Rafael Cruz in the background.

The Cruz campaign denied it was Rafael Cruz. Trump never provided any more evidence but, from time to time as the campaign wore on, would suggest that no one really ever totally solved the mystery. (There was no mystery, of course. Just Trump saying things.)

It's the sort of thing that, now that Trump and Cruz have made nice ( Trump is in Texas to hold a rally for Cruz tonight ), you might expect the President of the United States to apologize for.

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