Billy Carter appeared to relish his role as the president's colorful kid brother, raking in money through personal appearances, guest shots on TV's Hee Haw and even his own eponymous brand of beer.
When it came out that he had also accepted money for lobbying from the Libyan government, his financial dealings no longer seemed quite so funny.
Being related to a high-ranking politician can be lucrative, as former Vice President Joe Biden's son Hunter has discovered.
Hunter Biden accepted a seat on the board of the Ukrainian gas company Burisma Holdings, reportedly for $50,000 a month, despite no experience in the energy business.
But the younger Biden is hardly the first relative of a high-ranking politician to try to cash in on his or her famous relative's position.
"There have always been special interests looking for a shortcut to get access to power, and they're betting that the benefit that they get from hiring that relative will get them access and influence," says Meredith McGehee, executive director of Issue One, a nonpartisan group that seeks to reduce the role of money in politics.
Presidential relatives have been a source of scandal throughout history — in both Republican and Democratic administrations, she says.
When Richard Nixon first ran for president in 1960, he had to answer questions about a loan that billionaire Howard Hughes had given his brother Donald. Nixon later said the scandal had contributed to his narrow defeat to John F. Kennedy.
As President George H.W. Bush tried to deal with the fallout from the savings and loan crisis, he was also contending with an uncomfortable fact: His own son Neil had served on the board of Denver-based Silverado Savings and Loan, which went bankrupt, costing taxpayers more than $1 billion.
Like Billy Carter before him, Neil Bush insisted he had done nothing wrong, and no evidence emerged that he had received preferential treatment from the government.
But his role at the bank caused major political problems for his father.
Likewise, Billy Carter's ties to Libya led to a congressional investigation and caused a major scandal for his brother, who had come to office promising to run an honest administration after Watergate.
The fact that Billy Carter was never charged with any crime almost didn't matter, says presidential historian Julian Zelizer of Princeton University.
"Very often there's nothing wrong. Nothing is actually done that's illegal. Nothing is done that's formally unethical, and rarely has it affected public policy. But that's different than, 'Does it become a scandal?' It looks bad," Zelizer says.
Now, it's former Vice President Biden's turn to contend with a relative's questionable business dealings.
President Trump has vigorously sought to raise questions about Hunter Biden's activities. In fact, Trump's attempts to pressure Ukraine to investigate the younger Biden are at the center of the current impeachment inquiry against him.
But Trump has relatives making business deals too. Trump has never really separated himself from his family's business, the Trump Organization, which is run by his sons, Eric and Donald Jr., and the family has frequently been accused of seeking to profit off the presidency.
The Trumps' business dealings are even more questionable, Zelizer says, because Trump's daughter Ivanka and son-in-law, Jared Kushner, actually work in the White House.
"Billy Carter was not in the White House. He was not making decisions with the president, and that was the case with Neil Bush, too. So what we're talking about now is fundamentally different," Zelizer says.
MARY LOUISE KELLY, HOST:
Being related to a president or vice president can be lucrative. Take former Vice President Joe Biden's son Hunter. He got a seat on the board of a Ukrainian gas company despite having no experience in the energy business. He was paid $50,000 a month. NPR's Jim Zarroli looks at the long history of politicians' relatives trying to make a buck off their more famous family members.
JIM ZARROLI, BYLINE: Billy Carter owned a Georgia filling station when his brother Jimmy was elected president. He soon became famous in his own right - selling a brand of beer, doing personal appearances, even going on "Hee Haw."
(SOUNDBITE OF TV SHOW, "HEE HAW")
BILLY CARTER: (As self) But I still can't figure out what to do with the outside of a peanut. That's a whole problem.
ZARROLI: It was all in good fun until it came out that Billy Carter had taken money from Libya for lobbying work. Presidential historian Julian Zelizer.
JULIAN ZELIZER: And it explodes into this post-Watergate scandal - Billygate, it's called.
ZARROLI: Billy Carter insisted he'd done nothing wrong. He even made light of the scandal in a commercial later.
(SOUNDBITE OF ARCHIVED RECORDING)
CARTER: When I got $200,000 from Libya, a lot of people thought it was because of my brother. It's just not true. I was giving them advice. Whether you believe me or not, I'm going to give you some advice. Try Edy's Grand Light.
ZARROLI: Still, the revelation embarrassed President Carter. Lobbyists pay lots of money for access to a president, and Meredith McGehee of the campaign finance reform group Issue One says that's often meant going through their relatives.
MEREDITH MCGEHEE: And there have always been special interests looking for a shortcut to get access to power. And they're betting - right? - that the benefit that they get from hiring that relative will get them access and influence.
ZARROLI: Scandals over presidential relatives have happened in both Democratic and Republican administrations. Richard Nixon's brother Donald made headlines for taking a $200,000 loan from aviation billionaire Howard Hughes. Businessman Neil Bush was the son of President George H.W. Bush. He sat on the board of a savings and loan called Silverado that would later fail, costing taxpayers a billion dollars. Bush denied any wrongdoing.
(SOUNDBITE OF ARCHIVED RECORDING)
NEIL BUSH: I believe in the principle if you didn't do anything wrong, don't admit to it. And I didn't do anything wrong.
ZARROLI: There was never any proof that Neil Bush got preferential treatment from the White House. Still, it almost doesn't matter, says Julian Zelizer.
ZELIZER: Very often, there's nothing wrong. Nothing is actually done that's illegal. Nothing that is done that's formally unethical, and rarely has it affected public policy. But that's different than does it become a scandal. It looks bad.
ZARROLI: Today it's former Vice President Biden's turn. President Trump brings up Hunter Biden's financial endeavors all the time. Trump's efforts to get Hunter Biden investigated are central to the impeachment inquiry. Here's Trump at a recent rally.
(SOUNDBITE OF ARCHIVED RECORDING)
PRESIDENT DONALD TRUMP: Joe's son Hunter got thrown out of the Navy, and then he became a genius on Wall Street in about two days. By the way, whatever happened to Hunter? Where the hell is he?
ZARROLI: But Trump has relatives, too. And Zelizer says the Trump family finances are of a different magnitude. Not only are the Trumps still actively doing deals in foreign countries, Trump's daughter and son-in-law actually work in the White House.
ZELIZER: Billy Carter was not in the White House. He was not making decisions with the president. And that was the case with Neil Bush, too. So what we're talking about now is fundamentally different.
ZARROLI: The Trumps have actually embraced the idea that they can do business and still run the government. But for other presidents, drawing a line between the public interest and their family's finances has been a struggle.
Jim Zarroli, NPR News, New York.
(SOUNDBITE OF VALLIS ALPS' "RUN") Transcript provided by NPR, Copyright NPR.