Page Six reported that Hallie and Hunter began their relationship after the death of Hallie's husband of brain cancer in May 2015, a tragedy that weighed heavily on the tight-knit clan and reportedly contributed to the decision of Joe Biden not to run for president.
Hunter, a 47-year-old lawyer, is still married, though the tabloid reports that he and his wife, Kathleen, separated five months after Beau died.
Hunter made headlines over his discharge from the Navy Reserve after testing positive for cocaine in 2013.
It wasn't clear when the relationship between Hallie and Hunter began, though they are now an "official" couple, according to the report.
Hallie has two children; Hunter and his estranged wife, Kathleen, have three.
And despite the shock that greeted the report in Washington, DC, circles, the new couple apparently has the support of Joe and Jill Biden.
"We are all lucky that Hunter and Hallie found each other as they were putting their lives together again after such sadness," the former second couple said in a statement to Page Six.
"They have mine and Jill's full and complete support, and we are happy for them."
