It turns out the rumours were always true - America's 29th president had a love child.
New genetic tests reveal Warren Harding fathered a child with Nan Britton during his presidency.
The tests show that Harding, who was married, was indeed the father of Elizabeth Ann Blaesing, the late Britton's daughter.
His presidency ran from March 1921 until his death in August 1923.
Harding's immediate family and the public had rejected the claims and shamed Britton, calling her a liar.
Dr Peter Harding, one of the former president's grand-nephews who spearheaded getting the DNA tests done, told the BBC he is "totally jubilant" to finally know the truth about Blaesing's father.
"This has been a family mystery since I became aware of it," Mr Harding said.
"There was no way to really resolve it. Back in the 1920s, there was only whether someone looked like someone else."
He thinks advanced DNA testing was definitely conclusive. Mr Harding and his cousin Abigail Harding pursued the tests with James Blaesing, a grandson of Britton.
Blaesing died in 2005. Her mother wrote a book, The President's Daughter, in 1927, in an attempt to make money and prove Harding's paternity after his death at 57 as he had left no financial arrangement for their daughter.
"It is totally wonderful to vindicate her. She published her book when women just got the vote and people weren't believing women over powerful men," Mr Harding said. "Look how she survived this thing."
Britton was "vilified by everybody" for claiming President Harding's paternity, including by members of Mr Harding's family, he said, and he is "glad to reverse all that".
The scandal rocked the 1920s, also known as the "Roaring Twenties" - the president was married and much older than Britton.
"This is a wonderful feminist story, a woman who stuck to her guns and triumphed over 88 years," said Mr Harding.
In the past, the Blaesing family did not want to submit to DNA tests, thinking it insulting to their late matriarch.
Mr Harding hopes to meet more members of the Blaesing family soon and may see them at a family reunion.
"There's a whole lot of children and great-grandchildren of President Harding we've never met.
"There was something wrong in my whole family mystery I wanted to fix - it left a whole other family out in the cold which was intolerable to me."
Ancestry.com, which provided the test with their AncestryDNA service, confirmed the results were true to the BBC.