In an Instagram post shared with her more than 300,000 followers on Friday, McCain applauded her younger sister for having the courage to step up and add her voice in the battle against the President, claiming that her "strength and grace" has helped the family as they continue to grieve.
"Incredibly proud of my brave sister Bridget @bridgyyyyboo for speaking out against President Trump," she wrote. "I love you more than I could ever possibly say. Your strength and grace continues to help carry us all through our grief."
On Thursday, Bridget took her voice to Twitter to speak out after President Trump criticized the family of the late senator for not thanking him for "approving" John McCain's funeral last year after he passed away following a battle with brain cancer.
Bridget began her post by noting that not everyone has to "agree with my dad or like him," but that she and her family "do ask you to be decent and respectful," and, at the least, "be mindful. She also reminded those listening that she and her family had "only said goodbye to him almost 7 months ago."
"Even if you were invited to my dad's funeral, you would have only wanted to be there for the credit and not for any condolences," she continued. "Unfortunately, you could not be counted on to be courteous, as you are a child in the most important role the world knows."
Speaking on The View following her sister's comments, McCain had praised her "very, very private" sister for being brave and coming to their father's defense.
"I don't like coming here every day and having to do this...It's extremely emotionally exhausting," she said. "I'm not the only child in my family. I have six brothers and sisters. And my little sister Bridget, for the first time ever, has decided she wanted to speak out — she's very, very private."
"It's very brave of her," she added, noting that Bridget had stepped back from the spotlight following the 2000 presidential primaries. "She's very young and does not speak publicly."