Former Vice President Joe Biden opened up about the immense grief hes experienced since the loss of his son Joseph Robinette Biden III , better known as Beau, in an interview with Vanity Fair published on Wednesday.

Biden unpacks the loss of 46-year-old Beau from brain cancer on May 30, 2015, in his forthcoming book, Promise Me, Dad: A Year of Hope, Hardship, and Purpose. He spoke with Vanity Fair about the loss, his good friend former President Barack Obama , and the possibility of an upcoming presidential campaign.