WILMINGTON, Del. (AP) — First lady Jill Biden said in an email to campaign donors on Saturday she didn’t know what the special counsel was trying to achieve when he suggested President Joe Biden could not remember his son’s death.

”We should give everyone grace, and I can’t imagine someone would try to use our son’s death to score political points,” she wrote. “If you’ve experienced a loss like that, you know that you don’t measure it in years -- you measure it in grief.”

It was an emphatic defense of her husband in a note to supporters as Biden’s team worked to alleviate Democratic concerns over the alarms raised by a special counsel about Biden’s age and memory, in a report determining that Biden would not be charged with any criminal activity for possessing classified documents after he left office.

Special Counsel Robert Hur, a Republican former U.S. Attorney appointed by Donald Trump, found the president should not face charges for retaining the documents, and described as a hypothetical defense that the 81-year-old president could show his memory was “hazy,” “fuzzy,” “faulty,” “poor” and having “significant limitations,” and added that during an interview with investigators that Biden couldn’t recall ”even within years” when his oldest son Beau had died.

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“Believe me, like anyone who has lost a child, Beau and his death never leave him,” Jill Biden said.

It was an unusually personal observation for a special counsel investigating the president’s handling of classified documents. Beau Biden died in 2015 from a brain tumor, it’s something that Biden speaks of regularly, and cites as both a reason why he didn’t run in 2016 and a later motivator for his successful 2020 run.

“May 30th is a day forever etched on our hearts,” Jill Biden said in a note to supporters about the day Beau Biden died. “It shattered me, it shattered our family. ... What helped me, and what helped Joe, was to find purpose. That’s what keeps Joe going, serving you and the country we love.”

The references to Beau Biden in Hur’s report enraged the president, who later said: “How in the hell dare he raise that?”

Biden mentioned that he had sat for five hours of interviews with Hur’s team over two days on Oct. 8 and 9, “even though Israel had just been attacked on October 7th and I was in the middle of handling an international crisis.”

Voters have been concerned about his age. In an August poll by The Associated Press-NORC Center for Public Affairs, 77% of U.S. adults said Biden is too old to be effective for four more years. It was one of the rare sources of bipartisan agreement during a politically polarized era, with 89% of Republicans and 69% of Democrats saying Biden’s age is a problem.

“Joe is 81, that’s true, but he’s 81 doing more in an hour than most people do in a day. Joe has wisdom, empathy, and vision,” Jill Biden said. “His age, with his experience and expertise, is an incredible asset and he proves it every day.”