Hunter, 49, made headlines in 2017 when he began dating Hallie Biden, the widow of his brother,. Beau Biden, who served as attorney general in Delaware, died in 2015 of brain cancer.
The former vice president confirmed in 2017 the pair were dating, saying "we are all lucky that Hunter and Hallie found each other as they were putting their lives together again after such sadness." Joe Biden and his wife, Jill, said at the time the couple had their "full support."
Hunter and Hallie split in April, according to the Post and Page Six.
Hunter's daughter, Maisy, graduated from Sidwell Friends over the weekend, along with former President Obama's daughter Sasha. Hunter and his first wife, Kathleen, divorced in 2017.
Hunter has already made headlines since Joe Biden jumped into the presidential race. The New York Times reported last month that Hunter was getting paid as much as $50,000 from a Ukrainian energy company that was targeted by the country's top prosecutor — who Joe Biden pressured the government to remove. Ukraine's prosecutor general told Bloomberg there is no evidence of wrongdoing by the Bidens.
But despite the murky details, President Trump's lawyer Rudy Giuliani — who himself has various entanglements in Ukraine — at one point said he would go himself to Ukraine to get to the bottom of the story. He later called the trip off when he was criticized for trying to influence the 2020 election.
Hunter was discharged from the Navy in 2014 after he failed a drug test.
Adam Brewster contributed reporting.