The widow of Sen. John McCain pushed back against President Donald Trump’s continued attacks against the late Arizona Republican.

“The legacy and record of John McCain are under attack,” Cindy McCain, the senator’s wife, wrote in a fundraising email for the McCain Institute for International Leadership at Arizona State University.

“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,” Cindy McCain wrote.

Cindy McCain chairs the institute, which was founded seven years ago to research ways to stem human trafficking, advance human rights, and promote national and international security.

The fundraising email Thursday, which did not mention Trump by name, arrived in supporters’ inboxes a day after the president renewed his ongoing feud with McCain, who died from brain cancer last year.

During his speech in Lima, Ohio, on Wednesday, the Trump complained that he never received a thank you for McCain’s funeral in Washington.

“I gave him [McCain] the kind of funeral he wanted, which as president I had to approve. And I didn’t get a thank you. But that’s OK,” Trump said, adding that he “never liked” the former U.S. Navy fighter pilot who was tortured as a prisoner of war during the Vietnam War.

Watch: Trump: McCain got the funeral he wanted, and I ‘didn’t get a thank you’

Lawmakers from both parties have roundly criticized Trump for taking continual jabs at McCain, a longtime Arizona senator who was the Republican nominee for president in 2008.

Those condemnations range from 2020 Democratic presidential candidate Sen. Bernie Sanders of Vermont to Georgia Republican Sen. Johnny Isakson, chairman of the Senate Veterans’ Affairs Committee. 

“It’s deplorable what [Trump] said” regarding McCain’s time as a prisoner of war in Hanoi during the Vietnam War, Isakson told Georgia Public Broadcasting on Wednesday.

During the 2016 campaign, Trump said McCain was not a war hero.

“He’s not a war hero. He’s a war hero because he was captured. I like people that weren’t captured,” said Trump, who received a deferment from military duty during the war because of bone spurs in his feet. (Trump has never produced any medical records that confirm he had bone spurs.)

Isakson defended McCain’s military record again on Wednesday.

“There aren’t Democratic casualties and Republican casualties on the battlefield, there are American casualties,” Isakson said.

“We should never reduce the service that people give to this country including the offering of their own lives to any political fodder in Washington, D.C., or anywhere else for that matter,” he said.