Meghan McCain's apparent criticism of President Donald Trump at the memorial service of her father, Arizona Sen. John McCain, was in line with the late senator's outspoken style, two of his former Senate colleagues and friends told CNN on Sunday.
In her emotional speech at Saturday's funeral service — which Trump was not invited to attend — the younger McCain took veiled swipes at the president, blasting him for "cheap rhetoric" on American greatness. She never mentioned the president by name.
"The America of John McCain has no need to be made great again because America was always great," she said, emphasizing her father's vision of how he saw the nation during his service and appropriating the president's "Make America Great Again" campaign slogan.
"She is her father's daughter," Graham told CNN's "State of the Union" in a joint interview with Lieberman. "If you say something bad about her dad, you will know it, whether you're the janitor or the President of the United States. She is grieving for the father she adored. I think most Americans understand that."
Lieberman added that he was a "proud uncle" watching McCain's speech at the memorial service.
"She was direct ... the way John was," Lieberman said.
The senators' defense came after McCain posted a photo of them online, calling them her "uncles forever." Graham, Lieberman and McCain were often referred to as the "three amigos" during their time in the country's top lawmaking body.
In Sunday's interview, the two senators reflected on their friendship with the late senator and Navy veteran.
"His own attitude, the way he faced death with characteristic fearlessness and perspective, really comforted me," Lieberman said. "We're going to miss him. He's irreplaceable." Graham added that McCain's legacy in the Senate would live on.
"John loved the Senate," the South Carolina senator said. "He was a man of the Senate. He loved the institution. When you write the history of the Senate, he's going to be in the first chapter."
Trump infamously questioned the veteran Republican Senator's military credentials during the 2016 election cycle, stoking outrage by suggesting McCain was not a hero because he was captured by the Vietnamese.
—CNBC's Brian Schwartz contributed to this report.