Depending on the outcome of the US presidential election, America could have a new First Lady by the end of it.
In 1972 his wife and daughter tragically died in a car crash, which left his other two children seriously injured.
Years later, in 2015, his son Beau, who survived the crash, died from a brain tumour.
But one source of comfort and support for Joe has been his second wife Jill.
Dr Jill Biden has appeared regularly at rallies to support her husband’s campaign.
Here is all you need to know after the new potential First Lady of the US.
Who is Jill Biden?
Jill Biden, born Jill Tracy Jacobs, has been a teacher for most of her life.
She is also often described as Joe’s biggest defender and one of his biggest assets and one of his most trusted political advisers.
She gained a Doctor of Education degree from the University of Delaware in 2007, which she added to her bachelor’s degree and two masters degrees.
Jill has been working in teaching since the 1970s, at high schools, community colleges and even a psychiatric hospitals.
She plans to return to her role as English Professor at Northern Virginia Community College if her husband is elected president.
Jill and Joe tied the knot on June 17, 1977, after he had proposed five times.
She is 69 years old, nine years younger than her husband.
The two met on a blind date that had been arranged by Joe’s brother Frank, who had, like Jill, studied at the University of Delaware.
Jill told Vogue: “He was nine years older than I am! But we went out to see ‘A Man and a Woman’ at the movie theatre in Philadelphia, and we really hit it off.
“When we came home … he shook my hand good night … I went upstairs and called my mother at 1am and said, ‘Mom, I finally met a gentleman.'”
Jill had previously been married to Bill Stevenson, but their marriage broke down in 1974.
Jill and Joe have one daughter together – Ashley Blazer Biden, 39.
When they married, Jill became a stepmother to Joseph “Beau” Biden and Robert Hunter Biden.