Jan Karbaat, a fertility doctor in the Netherlands, died in 2017, but before that he became the father of at least 49 children. Contrary to the wishes of the patients, Carbaat used his sperm rather than the donors to fertilize in vitro women who could not conceive. After judges ordered the publication of Karbat's genetic profile, a group suspected of being a doctor's successor carried out fatherhood tests, out of which 49 found that they were indeed a child of late doctors.

Before dying, Karbaat admitted to being the father of 60 while serving at the fertility clinic. According to The New York Times, the term clinic probably does not fit the case. "Karbaat administered a sperm bank behind his yellow brick house in the town of Barendrecht, near Rotterdam." He helped concoct about 10,000 children from 1980 to 2009 when authorities closed the clinic for numerous violations.

In 2017, a group of so-called "Carbaat children" sued the doctor's family a month after the death of the latter. At that time, a judge decided to collect a doctor's DNA after death from personal items such as toothbrushes. The genetic profile would be kept isolated until another judge decides for the next step. In February, the district court ruled that there was much evidence that Karbaat used his sperm to inseminate the patients, and as a result, is the father of up to 200 children without the knowledge of their parents.

However, not all Karbat children feel bad about the event. "I do not think it deceived my mother," says Eric Lever. "She wanted a baby and could not get pregnant with my dad."

Others expressed grateful that it was over. "After an 11-year quest, I can continue my life," said a man named Joey. "I'm happy to finally know everything."