WILMINGTON, Del. (AP) — President Joe Biden on Wednesday honored the memory of his first wife and baby daughter 52 years after they were killed in a car crash in Delaware.

Biden's wife, Neilia, 30, had taken their kids — 1-year-old daughter Naomi and sons Beau and Hunter — out Christmas tree shopping when the car she was driving was broadsided by a tractor-trailer. Neilia and Naomi were killed. Beau, 3, and Hunter, 2, were gravely injured.

The president, his current wife, Jill, son Hunter and other members of the family attended a private memorial Mass early Wednesday at St. Joseph on the Brandywine Roman Catholic Church near Biden's home in Delaware. After the service, the family, with Jill Biden holding hands with Hunter's young son, Beau, walked to the cemetery behind the church where the gravesites are located.

Biden speaks often about the personal loss, sharing the story as recently as last week. He told of being in Washington with then-Sen. Edward Kennedy, D-Mass., when he got a phone call.

“I got a phone call from my local fire department, telling me there had been an accident,” he said at a White House dinner attended by members of Kennedy's family. "And the poor firewoman they put on the call for me said — I said, ‘How are they?' They said, ‘Uh, uh, um, she’s dead. Your daughter is dead. And I’m not sure your two sons will make it.’”

Biden, who had been elected to the Senate just weeks before the crash, talks about how he almost walked away from his congressional career before it even started. But he took the advice of other senators, was sworn in to office at his sons' hospital bedside and made a daily commute between Delaware and Washington on Amtrak.

Next month, Biden will close the book on a nearly 50-year career in elected politics and public service that includes 36 years in the Senate, eight years as vice president and four years as president.

His openness about his grief and coping with it, and his ability to empathize with others who have experienced loss, have become one of the hallmarks of his long political career.

Biden married Jill Jacobs in 1977 and she helped raise Beau and Hunter as if they were her own. Later, she and Biden added daughter Ashley.

Decades after that fatal car crash, Biden, as vice president, navigated through personal loss again when Beau Biden died of brain cancer in 2015 at 46. Beau Biden is also buried in the church cemetery.

President Joe Biden and first lady Jill Biden are greeted as they arrive at St. Joseph on the Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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Hunter Biden, his wife Melissa Cohen Biden and their son Beau are greeted as they arrive at St. Joseph on the Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed President Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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President Joe Biden, first lady Jill Biden and grandson Beau Biden walk from Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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President Joe Biden, first lady Jill Biden and grandson Beau Biden step out of Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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President Joe Biden, first lady Jill Biden walk from Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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President Joe Biden, first lady Jill Biden and grandson Beau Biden step out of Brandywine Catholic Church in Wilmington, Del., on Wednesday, Dec. 18, 2024. Wednesday marks the 52nd anniversary of the car crash that killed Joe Biden's first wife Neilia Hunter Biden and 13-month-old daughter Naomi. (AP Photo/Ben Curtis)

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