There's a reason Paul is in the position that he is today and Corey is not, and it is not because Paul is amateur hour," Donald Trump Jr. said. "I think it is nonsense. I heard that other people ask 'Oh, is the family on the outs with Paul?' Total nonsense."
Perhaps because of the possible backlash effect of speaking negatively about a Republican candidate's wife who has been reluctant to seek the spotlight, Democrats largely avoided commenting on the controversy on Tuesday.
While the Trump campaign released talking points on how to respond, most surrogates did not appear to take the campaign's lead.
Perhaps the most unusual response on the controversy came from former 2016 candidate Ben Carson, when he was asked about the plagiarism charge after addressing the Florida delegation breakfast.
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"I think what we should be thinking about is if Melania's speech is similar to Michelle Obama's speech, that should make us all very happy because we should be saying whether we're Democrats or Republicans, we share the same values," Carson said. "That's what we should be talking about. Not trying to make it controversy."
CNN's Ashley Killough and Eugene Scott contributed to this story