As Hunter Biden’s paternity scandal drags on and President Biden appears to ignore his out-of-wedlock grandchild, the pair are doing the child a disservice against the backdrop of a century of progress for unwed mothers.

Earlier this month, Hunter Biden appealed to a judge in Arkansas in a bid to lower his monthly child support payments to former stripper Lunden Roberts who bore him a daughter — Navy — in 2018. 

In centuries past, Ms. Roberts and her daughter would have been out of luck. Never mind that Hunter Biden prices (and appears to sell) his paintings for up to half a million dollars. Ms. Roberts and daughter would have had no claim on his earnings, with only her word against that of a powerful man of privilege. 

Today, DNA has “established with scientific certainty” that Hunter Biden is Navy’s father. The days when he’d have felt societal pressure to marry the mother may be gone. Hunter Biden married someone else a year after Navy’s birth. His new wife, Melisssa Cohen, bore him a son in 2020. Public opinion and courts still hold deadbeat parents to account.

In the 1884 presidential election, there was no test to settle the truth when Maria Halpin claimed President Cleveland had gotten her in “a family way.” Cleveland didn’t deny it, but his partisans responded that Halpin had been generous with her affections — a familiar rebuttal — as Republicans taunted him with the chant, “Ma, Ma, where’s my Pa? Off to the White House. Ha! Ha! Ha!”

“The circumstances under which my ruin was accomplished,” Halpin told the Chicago Tribune, “are too revolting on the part of Grover Cleveland to be made public.”

After the news hit in September — a Gilded Age October Surprise arriving before its due date — a column ran in The New York Sun under the byline “From the Christian at Work” calling Cleveland “a self-confessed destroyer of womanhood.”

Democrats attacked Halpin, employing a version of what the head of the National Organization for Women, Patricia Ireland, decades later criticized as President Clinton’s “nuts and sluts defense” against women accusing him of misconduct.

Modern historians have a kinder view of Ms. Halpin, who had her son torn from her to be adopted away and was sent to a mental asylum amidst the effort to support the insanity narrative. The boy, James E. King, died childless in 1957, making a DNA resolution difficult short of an exhumation.

Another surprise was delivered the October before the 1920 election, when President Harding’s mistress, Nan Britton, gave birth to a daughter, Elizabeth Ann, in secret. With Harding having died in the second year of his presidency without providing for the child, Britton wrote in 1927 the first tell-all book, “The President’s Daughter.”

Britton wrote that her goal was to provide for her daughter and champion “legal and social recognition and protection of all children born out of wedlock.” She also called for legislation so the names of fathers could be “correctly registered in the public records,” rather than left blank to protect men from scandal.

Britton remained in love with Harding until her death in 1991, having withdrawn into seclusion to avoid the abuse heaped on her after publication. Elizabeth Ann’s son, James Blaesing, took a DNA test in 2015, proving that Britton had been telling the truth.

Mr. Biden and Hunter have done much to undo the legacies of Britton and Halpin, with the president gushing about his “six grandchildren” — not seven — and hanging stockings at the White House for them but denying Ms. Roberts’ daughter even that small kindness.

The denial of his granddaughter’s existence is striking from Mr. Biden who often boasts of giving “my word as a Biden,” as if the family name is of great import, even as his son fights to prevent Ms. Robert’s daughter from using his surname.

A small mercy for Ms. Robert’s daughter is that she’s too young to understand rejection, but she will one day ask, “Ma! Ma! Where’s my Pa?” With thanks to the women who came before her, she’ll be able to echo with confidence the jibe, “Off to the White House. Ha! Ha! Ha!”