All it may take is a simple look at your wrist to bond with a stranger on the internet.
Twitter user Aaryn Whitley had plenty of people realizing they have something in common when she posted four pictures of different women's arms with a single freckle in the same spot.
"ladies..... u got a freckle on the middle of ur wrist or is this a myth lmao,'' she wrote.
That prompted a group of men and women to share photos of their own wrist freckle. A handful of folks were "low key freaking out" after finding out they weren't the only ones.
Freckles get darker in the summer, so now may be the perfect time to compare those wrist spots.
The reason why so many people seem to share the mark could be as simple as it's a body part that's regularly exposed to the sun. Other than that, no one seems to know.
The sun's ultraviolet rays stimulate the skin’s pigment-forming cells to produce more melanin in the skin, but they will only form in those who are genetically predisposed to them, skincare expert Dr. Howard Murad told TODAY in 2014. Sharing that wrist freckle also means sharing that tiny genetic similarity.
Those same-looking wrist freckles also have formed over time because nobody is born with freckles. They usually don't start popping up until adolescence.
While seeing plenty of others with the same wrist freckle might be a little freaky, the main concern is making sure to protect your skin from the sun with a broad-spectrum SPF.
"You have inherited a predisposition to freckles, and you are likely to get more of them — in addition to risk of skin cancer — if you don’t use sun protection," Los Angeles dermatologist Dr. Jessica Wu told TODAY.