A friend is a programmer, or rather, a database architect. He once designed the structure of a base for some German pro-government organization. Knowing of the rise of Western tolerance, he programmed them up to 10 parents per child and up to 40 gender options.

“You’ve gotten too old,” the Germans say to him. - Parents we have, as appropriate, from one to two, and the gender options are four: male, female, other and "not specified". But the base will not go anyway, we need to rebuild. The number of children is wrong.
What does it mean wrong?
The whole number.
What do I need?
It is fragile.

A friend’s roof was touched. 10 parents he could still poorly imagine. Dad, mom, new mom’s husband, new dad’s wife, two grandmothers and two grandparents – here’s already 8. But one and a half earthquakes, that is, one and a half children – this is, forgive me, how? One whole and one without a leg. Or do they consider 5 months of pregnancy to be 5/9 child?

It turned out, it was easier. German tax law. Each child is subject to a tax deduction, but if both parents submit declarations separately, this deduction is divided between them in half. That is, the child of a single mother is a whole unit, and if two parents are both working, then each gets half a child. And that database was related to taxpayers, so we needed such a county.

By the way, the notorious “parent number 1” and “parent number 2” are also invented not for gay perversions. Parent number 1 is the one to whom kindergarten or school appeals first in case of need. Usually this is the mother, but if, for example, the parents are divorced and the child lives with the father, then the first parent will be the father. And if, don’t give god, the father and mother died or are absent for another reason, then the parent number 1 may be a grandmother or an adult sister. A family of two mothers or two fathers also fit conveniently in this scheme, but such families are significantly fewer. Don’t look for a black cat where it isn’t.