Sometimes you think you know all there is to know about the world, then something like this comes along and blows all your preconceptions away, and you realise there’s a LOT you do not know.

Frankly I’d never considered the idea of twins having different fathers; I just took it for granted that they always do. Apparently, that’s not the case.

A judge in New Jersey ruled that a man who was being sued for child support, only had to pay it for one of a pair of twin girls. A paternity test ordered by the judge showed that he was the biological father of only one of them.

NBC NY reports that only two of such cases were fund in the annals of US legal history. Such a situation is possible if a woman has seks with two different men within one menstrual cycle, and both fertilises an egg in her.

The woman had admitted to sleeping with two men around the time she conceived, and the man was found as being responsible for only one of the twins.

The judge ruled that he’s to pay $28 child support every week.