We like to think that we know everything about our favorite celebrities, but sometimes they hold their secrets pretty close.
Like all of us, celebrities have unique medical histories. Sometimes, they're left with unusual or odd body parts.
And while some people might be shy, these stars proudly showed off their sometimes freaky features.
1. Drew Carey - Extra Toes
The Price is Right host bragged in his autobiography Dirty Jokes and Beer that he was born with six toes on his right foot.
Called polydactyly, extra digits on hands and feet are more common than you might think, affecting 1 in 500 babies.
Usually, the bonus digits are fleshy and boneless, so they're easy to remove.
Private Practice star Taye Diggs was born with 12 fingers - six digits on each hand - and the extras were removed in his childhood.
The piano-playing actor joked he could have been "really handy" if he kept them.
2. Jane Seymour - Mismatched Eyes
The actress, who played the lead role in Dr. Quinn, Medicine Woman, is one of the most famous people with heterochromia.
The rare condition - less than 200,000 people in the U.S. have it - is harmless, but causes the eyes to have different colors.
Other stars have mismatched eyes from chronic conditions or serious injuries.
Mila Kunis had an irritated iris, and the surgery to correct it left one of her eyes a different color.
Meanwhile, singer David Bowie had one of his eyes permanently discolored by a punch in the face during his teenage years.
3. Daryl Hannah - Missing Finger
The Splash and Wall Street star wore a prosthetic while filming some of her biggest roles, to hide the result of a childhood accident.
Hannah lost the top of her left index finger to an injury from her grandmother's stair lift.
The actress says the almost unnoticeable detail "has bestowed on me an ability to be a more compassionate person."
But she's not the only star with a clipped digit.
Vince Vaughn lost the tip of his thumb in a car accident at age 17. The injury inspired him to pursue acting instead of water polo.
And Friends star Matthew Perry lost the tip of his right middle finger as a child, when it was caught in a door.
4. Joaquin Phoenix - Cleft Lip
Joaquin Phoenix, who played Johnny Cash in Walk the Line, is famous for the scar above his top lip.
While most people assume the star was born with a cleft lip or palate, the actor insists it's actually just a birthmark.
A cleft is formed when two sides of the lips do not fuse properly in the womb. They affect 2 in every 1,000 babies.
Football star Peyton Manning also famously has a cleft lip.
5. Carrie Underwood - Third Nipple
A surprising number of celebrities were born with this odd birthmark, called a supernumerary nipple by doctors.
Country star Carrie Underwood admitted her extra feature to the American Idol judges during her first audition.
"It just looked like a mole," she explained.
Other celebs with third nipples include Zac Efron (who had his removed) and Mark Wahlberg (who calls it his "prized possession").
But One Direction singer Harry Styles has four nipples.
"It must have been a twin," he explained, "but the other one went away and left its nipples behind."
6. Andy Garcia - A Conjoined Twin
Speaking of missing twins, The Untouchables actor Andy Garcia had his twin removed as a child.
The actor was reportedly born with an undeveloped, conjoined twin attached to his shoulder.
The growth, said to be the size of a tennis ball, was surgically removed, but since he was so young Garcia says he has no memory of it.
Unlike conjoined twins, Garcia's growth is called a parasitic or heteropagus twin, because it was not fully formed.
7. Ashton Kutcher - Webbed Toes
As the That '70s Show star quipped, "When everything else is this good looking, something's got to be messed up!"
Kutcher showed off his "slightly" webbed toes on a British talk show and seriously disgusted the host.
Webbed feet, also known as syndactyly, occurs in 1 in 2,500 live births, and is totally harmless.
Children usually have webbing removed with cosmetic surgery, but minor webbing like Kutcher's is sometimes left alone.
8. Stephen Colbert - A Lame Ear
The Late Show host loves to show off his completely limp right ear, which he can fold up inside itself and "pop out" by moving his head.
The reason for his unusual feature was a childhood surgery that also left Colbert deaf on the right side.
The host joked with David Letterman that doctors had to "scoop it all out with a melon baller."
"This is just a prop," he added. "t doesn't work at all ... It's all gone. Nothing in here."
Actor Gerard Butler also has a famously floppy ear, left over from his own childhood surgery.
He admits his makeup artists have to literally glue his left ear to his head on set.
9. Seal - Lupus Scars
Despite the rumors you might have heard about the "Kiss From a Rose" singer's facial scars, there's no scary story behind them.
The scars are actually caused by a genetic condition called discoid lupus. The autoimmune disease leaves a signature "butterfly" rash over the cheeks and nose.
Seal underwent treatment for the condition at age 23, and hasn't suffered any nasty flare ups since then.
10. Paris Jackson - Unusual Eyes
The late Michael Jackson's daughter is charting her own path through the music business, and developing a huge fan following on Instagram.
A striking part of the singer's appearance are her eyes, which are an almost unnatural shade of icy blue.
Her makeup artist, Jo Baker, says a rare genetic condition is behind the bold color.
Waardenburg Syndrome, which affects 1 in 40,000 people in America, has two major symptoms: bright blue eyes and hearing loss.
Hopefully, Jackson isn't experiencing much of that second symptom.
11. Denzel Washington - A Seriously Broken Pinky
Washington has starred in many fast-paced action movies, which might explain why you never noticed his "magic finger."
The star says his right pinky finger was injured over and over playing football, and he never had it set properly.
While the damage is not immediately noticeable, when Washington flexes his hand the pinky pops out and bends at a 45 degree angle.
Co-stars have said Washington likes to prank them by popping his finger out as a gag.
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