Kevin Bacon

After 25 years of marriage, Footloose actor Kevin Bacon found out that he and his wife, actress Kyra Sedgwick, are distant cousins. According to The Independent, the couple discovered their familial connection on Finding Your Roots, a show on PBS that shows celebrities their ancestral backgrounds.
On their episode, Bacon and Sedgwick were shown how their families are connected to major moments in American history, including the Declaration of Independence. However, it was also revealed to them by their DNA analysis that the actors are related to each other, specifically as ninth cousins once removed.
Upon learning the shocking revelation, Sedgwick said, “as long as we’re not first cousins, it’s fine.”
Franklin Delano Roosevelt

It’s no secret that President Franklin Roosevelt and First Lady Eleanor Roosevelt were cousins. According to History, Franklin and Eleanor were fifth cousins and first met when they were young children and became very close…perhaps too close. In 1902, 22-year-old Franklin proposed to 19-year-old Eleanor; they wed on St. Patrick’s Day two years later.
Though they are remembered as one of the most powerful political couples, the Roosevelts’ marriage was hardly romantically intimate. Franklin had a long-term affair with Eleanor’s secretary, Lucy Mercer, along with other women throughout his life. Meanwhile, Eleanor was rumored to have a secret romance with her friend, Lorena Hickock.
Woody Allen

Technically Woody Allen and Soon-Yi Previn aren’t biologically related, but that doesn’t make their relationship any less creepy.
The love affair began in 1992 when Soon-Yi was in her early 20s and Allen was in his 50s. Allen, at the time, was in a long-term relationship with Soon-Yi’s adoptive mother, Mia Farrow. Allen and Farrow never married but had two children together, an adopted daughter Dylan and a biological son Satchel (Ronan). According to Vox, Dylan would go on to accuse Allen of abuse while Ronan won the 2018 Pulitzer Prize for Public Service for his role in exposing the Harvey Weinstein assault allegations and igniting the #MeToo movement.
Allen and Soon Yi’s affair was discovered when Mia found nude photos of Soon-Yi in Allen’s apartment and Allen has been under scrutiny ever since. Allen and Soon-Yi married in 1997 and have two adopted children.
Thomas Jefferson

There are mixed views on Thomas Jefferson as a President and as an American founding father. On one hand, he is praised for penning the United States Declaration of Independence. On the hand, he has been criticized for his ownership of slaves.
What many people don’t know, however, is that, according to the New England Historic Genealogical Society, Jefferson was also married to his third cousin, Martha. The Jeffersons had six children, but only two of them actually reached adulthood. After Martha’s death, it is believed that Thomas had an affair with his slave, Sally Hemmings, who was believed to be Martha’s half-sister.
Rudy Giuliani

Long before he was mayor of New York City, Rudy Guiliani was married to his second cousin, Regina Peruggi. According to Politifact, they got married in 1968 and divorced 14 years later.
Buzz about his blood connection to his first wife resurfaced when a video called “Debate 08: Obama Girl vs. Guiliani Girl” went viral. In the video, two women lip sync and debate about the quality of their preferred candidate for the 2008 Presidential Election. At one point, the girl in Obama’s corner said, “Guiliani Girl, just stop your fussing, at least Obama didn’t marry his cousin.”
Guiliani and Peruggi never had children in their years together, which is probably a good thing considering offspring of second cousins is just about as risky as offspring of first cousins.
Albert Einstein

Even though Albert Einstein is considered to be the “Father of Modern Physics,” you probably shouldn’t model your relationships after his.
When Einstein was married to physicist Mileva Maric, he began an affair with Elsa Löwenthal…who was his cousin. According to ATI, Albert’s familial relationship to Elsa is especially strange because not only are they first cousins on their mothers’ side, but they are also second cousins on their fathers’ side.
To make matters even weirder, Albert developed a deep infatuation with Elsa’s daughter, Ilse, and even considered breaking up with Elsa to propose to Ilse instead.
Jerry Lee Lewis

Perhaps one of the most notorious incestuous celebrity relationships of all time was the marriage of Jerry Lee Lewis and Myra Gale Brown, Lewis’s 13-year-old first cousin once removed. She still believed in Santa Clause at the time of their marriage.
According to Medium, Lewis was on track to becoming the biggest rock and roll star in America. However, his career came to a screeching halt when the British press found about his relationship with his teenage cousin while on tour in the UK. The tour ended up getting canceled after a few dates and Lewis was practically driven out of the country by tabloids labeling him as a “cradle robber.” Their return to the United States was met with hostility as Lewis’s fans were also extremely critical of the relationship.
Ten years and two children later, Jerry Lee and Myra divorced amicably. They are still friendly to this day because, after all, blood is thicker than water.
Queen Elizabeth II

Historically, it wasn’t uncommon for royals to marry relatives, so Queen Elizabeth II’s marriage to her third cousin Prince Phillip isn’t all the surprising. In fact, in many cases, royals were required to marry a relative in order to keep their eligibility for the throne. According to Business Insider, both Elizabeth and Phillip are directly related to Queen Victoria. Elizabeth is the great-great-granddaughter of Victoria on her father’s side, while Phillip is a descendant of Victoria on his mother’s side.
Now, the rules have loosened up quite a bit and many royals in recent years have married commoners.
Edgar Allan Poe

Like Jerry Lee Lewis, Edgar Allan Poe also married his 13-year-old cousin, Virginia Clemm. At the time of their marriage, marrying your cousin was completely legal in all fifty states, however, their marriage was still controversial because Edgar was twice Virginia’s age when they wed.
According to The Airship, there is speculation that the Poe’s marriage had more of a sibling-like bond than a romantic one. They never had any children together, nor did their letters to each other ever allude to physical intimacy.
Edgar and Virginia stayed together until her death from tuberculosis when she was 24. It is said that she was the inspiration for some of Poe’s most famous works, including “The Raven” and “Annabel Lee.”
Charles Darwin

Perhaps the most ironic case of a notable person partaking in incest is Charles Darwin, who is famously known for his theories on evolution. Despite the fact that Darwin theorized that inbreeding plants would make them susceptible to disease, he didn’t seem to apply that knowledge to his own life.
According to NPR, Darwin married and had ten children with his first cousin, Emma Edgewood. Only seven of their children lived past the age of ten and three of the remaining seven were infertile. Studies suggest his children died or were infertile because they were inbred.