(CNN) John Kelly hasn't been chief of staff to President Donald Trump for even a year yet, but he appears to have learned one of the real estate tycoon's most central life lessons: Never, ever apologize.

"I have absolutely nothing to even consider resigning over," Kelly told reporters at the White House on Friday in response to questions over his botched handling of the allegations of domestic abuse against former White House staff secretary Rob Porter.

Kelly's defense -- and defensiveness -- simply doesn't jibe with what we know of the timeline of events surrounding Porter's firing.

Kelly told reporters that the first time he heard of the "serious accusation" against Porter came on February 6 -- the same day Porter resigned. But we know from CNN's own reporting that Kelly had some knowledge of the allegations against Porter long before that -- as far back as the fall of 2017.

And according to the Daily Mail's David Martosko, whose publication broke the news about abuse allegations against Porter, the first accusation against Porter that the Daily Mail took to the White House was from Jennifer Willoughby, one of Porter's ex-wives, who claimed Porter "physically dragged her, naked, out of a shower."

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