Hunter Biden has begun a romance with Hallie Biden, the widow of his late brother Beau. Picture: Astrid Stawiarz

Hallie Biden was devastated when her husband, Beau, died from brain cancer in May 2015. But she has since struck up a romance with Beau’s brother Hunter, 47, who has separated from his wife, Kathleen, the New York Post reported.

The astonishing family drama caps a difficult period for the Bidens following the death of Beau at age 46. The former vice president cited the death of his elder son as one of the reasons he decided in October 2015 against running for president.

Then US President Barack Obama shares a laugh with Vice President Joe Biden and Biden’s son Hunter Biden. Picture: Mitchell LaytonSource:Getty Images

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Former Vice President Biden confirmed the relationship to the New York Post said that he and his wife, Dr Jill Biden, have given their blessing to the couple.

“We are all lucky that Hunter and Hallie found each other as they were putting their lives together again after such sadness. They have mine and Jill’s full and complete support and we are happy for them,” Joe Biden said in a statement exclusively given to the New York Post.

Beau Biden celebrates winning his re-election bid for Delaware Attorney General with his wife Hallie Biden on November 2, 2010. Picture: Mark WilsonSource:AFP

Hunter, a lawyer, who has three daughters Naomi, Finnegan and Maisy with estranged wife Kathleen, also told the Post: “Hallie and I are incredibly lucky to have found the love and support we have for each other in such a difficult time, and that’s been obvious to the people who love us most. We’ve been so lucky to have family and friends who have supported us every step of the way.”

Beau, the former attorney general of Delaware, and Hallie have two children, Natalie and, confusingly, Hunter.

Former US Vice President Joe Biden, right, with his son, US Army Capt. Beau Biden, at Camp Victory on the outskirts of Baghdad, Iraq, on July 4, 2009. Picture: Khalid MohammedSource:News Corp Australia

A source told the New York Post that Hunter and Kathleen Biden separated in October 2015, five months after Beau’s death and around the time that Joe Biden decided not to make a presidential run. It is not clear if the estranged couple has yet filed for divorce.

Kathleen, chairwoman of the Washington DC-based Eleanor Roosevelt Dialogue, did not comment.

This story originally appeared in The New York Post nas has been republished with permission.