Thomson Reuters
The younger Biden's death was announced in a statement from the office of the vice president Saturday night.
Beau Biden, 46, served as Delaware's attorney general for eight years before joining the investor law firm Grant & Eisenhofer this year.
He had been hospitalized on several occasions in recent months.
A statement from Joe Biden's office reads in part: "The entire Biden family is saddened beyond words. We know that Beau's spirit will live on in all of us, especially through his brave wife, Hallie, and two remarkable children, Natalie and Hunter."
Beau had apparently been admitted to Walter Reed Army Medical Center for treatment earlier this month, but the details of that hospitalization were not disclosed at the time. He suffered what was classified as a mild stroke in 2010.
Beau Biden's death is another blow to the vice president, who lost his wife and child in a car crash shortly after his Senate election in 1972.
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