It may not come as a huge surprise that the royal family is actually quite a small circle.

Did you know, for instance, that according to Express, the late Queen Elizabeth II and her husband of three-quarters of a century, the late Prince Philip, were related? Indeed, the former heads of the British royal family were cousins, descended from Queen Victoria, as well as King Christian IX of Denmark, making them cousins twice over!

Meanwhile, King Charles and Queen Consort Camilla, who married in 2005, are also related. They are ninth cousins once removed via the family line of Henry Cavendish, the 2nd Duke of Newcastle, per Express.

And yes, Diana and Camilla are also related! See, small world, right? So how are they related? Well, both of the monarch's wives are descended from Charles II, who ruled in the 17th century.

Adding to the seemingly-small family tree intrigue of the royal family is that Diana, too, was related to Charles!

They are seventh cousins once removed via the relative William Cavendish, 3rd Duke of Devonshire.