Cindy McCain defended her late husband's legacy and integrity in an email to supporters in the face of a barrage of verbal attacks from President Donald Trump.
Trump has spoken ill of the late Sen. John McCain several times since last weekend, even saying he was responsible for giving McCain "the kind of funeral that he wanted."
Cindy McCain is now fighting back, although she did not mention the president by name.
"If there was a single word that mattered more to John than any other, that word may very well have been 'integrity.' John strived to live each day of his life with the utmost integrity — from his early days in the United States Navy, to defending our country and standing with his fellow POWs in Vietnam, to being a statesman of the U.S. Senate and representing America around the world," she wrote.
"Friends, the legacy and record of John McCain are under attack. Through the years, many of you heard John say 'a fight not joined is a fight not enjoyed.' Today, the fight we are fighting is for John's integrity, his record and his legacy.'"
McCain asked supporters to donate to the McCain Institute for International Leadership at Arizona State University, saying the organization is "the front line in defending the American ideals that my husband cherished."
John McCain, who spent five and a half years as a POW during the Vietnam War, died at age 81 last August after a battle with brain cancer.