Meghan McCain stood up for Chrissy Teigen after President Trump slammed the model for having a "filthy mouth."

"Since when is there something wrong with being a filthy mouthed wife? #teamchrissy," she tweeted Monday.

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"The View" co-host has long feuded with Trump over his repeated insults targeted at her late father, Sen. John McCain (R-Ariz.). Her support for Teigen came after Trump called out singer John Legend and Teigen, to whom Trump referred to as Legend's "filthy mouthed wife."

Trump wasn't happy that Legend and Teigen were “talking now about how great” crime reform is but allegedly didn't act on the reforms when Trump claims that it mattered. Trump signed the First Step Act into law last year, reducing mandatory minimum sentences in certain instances and giving judges more discretion in individual cases. More than 3,100 inmates will be released under the act, which has been praised by both Republicans and Democrats.

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Trump talked about criminal justice reform and how President “Obama couldn’t come close” to passing meaningful law. The president said he is tired of “boring musician John Legend” and his wife for touting the bill, which Legend discussed in a CNN special.

"They only talk about the minor players, or people that had nothing to do with it...And the people that so desperately sought my help when everyone else had failed, all they talk about now is Impeaching President Trump," Trump lamented.

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Legend responded to Trump’s tweet by appealing to first lady Melania Trump.

“Imagine being president of a whole country and spending your Sunday night hate-watching MSNBC hoping somebody—ANYBODY—will praise you. Melania, please praise this man. He needs you,” he tweeted. A minute later he tweeted, “Your country needs you, Melania.”

CHRISSY TEIGEN, JOHN LEGEND HEADLINE HOUSE DEMOCRATIC CAUCUS

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Teigen mocked the president, calling him a “p—y a— b—h” for tagging “everyone” but her in his tweet. Legend sarcastically requested that followers not retweet Teigen's insult as a hashtag.

The couple has been fiercely critical of the president for years. The Grammy winner called Trump a “piece of s—t” and a "canker sore on the country" after the president’s criticism of Baltimore.

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In an interview with USA Today, Teigen quipped, "I've actually been a big Donald Trump hater [for a long time]. I've been trolling him for about five to seven years now," she said. "I've been doing this forever, and I take pride in that."

Fox News' Edmund DeMarche contributed to this report.