Donald Trump has taken the unprecedented step of requesting his son-in-law, Jared Kushner, receive top-secret clearance to join him for his Presidential Daily Briefings, which began Tuesday.

Multiple sources tell NBC News Trump received his first briefing on Tuesday and designated both Kushner and Ret. Gen. Michael Flynn as his staff-level companions for the briefings going forward.

While Flynn has the necessary security clearance, Kushner does not, and it could take weeks — or even longer — for him to receive it.

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It's the latest in a series of unorthodox developments in Trump's transition process that have cast a pall over his first week as president-elect.

On Tuesday, former Rep. Mike Rogers announced he was leaving the transition team, as part of what sources close to the transition process told NBC News was a "purge" of loyalists to New Jersey Gov. Chris Christie, who was demoted from leading the effort last week due in large part to grudges held by Trump and Kushner, sources say.