Chelsea Clinton defended White House adviser Kellyanne Conway after a Democratic congressman, Rep. Cedric Richmond, made a distasteful joke about Conway being on her knees in the Oval Office.

Clinton wrote on Twitter, “Despicable. I hope [Kellyanne Conway] receives the apology she deserves-certainly never thought I’d write that & I mean every word”:

Conway thanked Clinton on Twitter after she expressed disappointment in the lack of “sisterhood” support over Richmond’s (D-LA) sexist comments about her:

“Thank you, @ChelseaClinton. As strong women, as moms to Charlottes…appreciate you speaking out on this,” she said.

Clinton has become an unlikely Conway supporter, as she has mocked her and the Trump administration on Twitter in the past.

During a speech at the Washington Press Club Foundation dinner Wednesday, Rep. Richmond said Conway “looked kind of familiar” kneeling on the Oval Office couch.

“You even mentioned Kellyanne and that picture on that sofa,” Richmond said. “I really want to know what was going on there because she really looked kind of familiar in that position there, but don’t answer.”

While Richmond said he was merely making a joke, his joke was not well-received by the crowd and on social media.

Conway called his joke “sexist and unfunny” while numerous others on social media, including Republican National Committee chair Ronna Romney McDaniel, condemned the congressman for his comments.