Beau Biden, who followed his father, US vice-president Joe Biden, into politics has died of brain cancer less than two years after he was diagnosed.
Beau Biden (inset), who was twice elected attorney general of Delaware, was 46.
He had suffered a series of health problems in recent years, and was admitted to hospital this month at Walter Reed National Military Medical Centre in Washington.
He suffered a mild stroke in 2010 and three years later underwent surgery at a Texas cancer centre to remove what was described as a 'small lesion'.
He announced last year that he would not seek a third term as attorney general and planned to run for governor in 2016.
"It is with broken hearts that Hallie, Hunter, Ashley, Jill and I announce the passing of our husband, brother and son, Beau, after he battled brain cancer with the same integrity, courage and strength he demonstrated every day of his life," the vice-president said.