This is what the children of two pairs of identical twins look like

An astonishing story emerged from Ohio, USA, in 1998. Identical twins Craig and Mark Sanders met two beautiful sisters who were also identical twins, Diane and Darlene Nettemeier, in a bar and understood that this was fate.

The two pairs of twins began to go on dates, and within a short space of time were married on the exact same day, in the exact same outfits. The two couples then set up home in neighboring houses, built a fence between them, and began to live like one large happy family.

After a year, Diane and Craig had identical twin children. Generally speaking, identical twins are born in 3 out of every 1,000 families, but the chances of identical twins themselves giving birth to identical twins are one in a million.

Not long after, Mark and Darlene became the parents of two beautiful twin girls, and a couple of years after that they had a son.

A fascinating scientific fact is revealed by this family’s experience: both pairs of parent-twins have the exact same selection of genes — that is, they are literally identical in physical terms. In turn, it works out that their two sets of children are as genetically close to each other as brothers and sisters are, yet they are formally cousins.

The chances are that many people expected to see two "symmetrical" families with identical children here, but this is actually impossible. An individual’s physical appearance is the result of combining various genes, and some of them can be passed on an additional generation down the line — from great-grandparents, for example. So absolutely identical children, in genetic terms, by definition cannot exist — even if we’re talking about two pairs of identical twins having kids together.

Today, this unusual family continues to live happily in two neighboring houses and often find themselves the subject of TV reports and documentaries.