Michelle Obama to Trump: Your history as a birther can't be 'swept under the rug' with 'an insincere sentence'

Michelle Obama on Wednesday sustained her critique of Donald Trump for the Republican nominee's years of openly questioning whether her husband, President Barack Obama, was born in the United States.

Speaking to a crowd in Philadelphia at a campaign event for Hillary Clinton, the first lady again laid into Trump's questions about her husband's birthplace, which she labeled as "hurtful, deceitful questions deliberately designed to undermine his presidency."

"Questions that cannot be blamed on others or swept under the rug by an insincere sentence uttered at a press conference," Michelle Obama said, referencing a press conference earlier this month in which Trump declared he now believed that the president was born in the US. At the same press conference, Trump also praised his ability to force the president to share his birth certificate.

The Obamas through the years:

"I think Barack has answered these questions with the example he set and the dignity he's shown," Michelle Obama said on Wednesday.

The first lady also took a swipe at some of Trump's statements during the debate, saying the president needed to be someone who would act like "an adult" and "study and prepare." She criticized Trump's suggestion that he was smart for paying no income taxes in the past, as well as his comments about a Miss Universe model whom Trump said was a "real problem" after she gained weight following her pageant win.

"If a candidate is erratic and threatening, if a candidate traffics in prejudice, fears, and lies on the campaign trail, if a candidate thinks that not paying taxes makes you smart, or that it's good business when people lose their homes, if a candidate regularly makes cruel and flippant comments about women, about how we look, and how we act, then sadly that's who that candidate is," Michelle Obama said.

Michelle Obama has hit the trail repeatedly for Clinton, stumping at rallies in front of largely Millennial audiences in battleground states like North Carolina and Pennsylvania.

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