But the only sperm he used was his own, dozens of times, resulting in at least 94 offspring when counting stopped in 2017.
In the small part of Indiana where Dr Cline's deception took place, almost anyone in the local community between the ages of 10 and 50 could be closely related.
Jacoba Ballard, in her 40s, spearheaded the inquiry into Dr Cline's practices. After being prompted to take home a DNA test kit, she learned she had seven half-siblings who she'd never heard of before. She'd wanted siblings and was delighted at first, but then she discovered the awful truth that Dr Cline was in all seven cases, their father. Who else was related to them?
In 2014, the seven banded together and discovered there were many more than the seven of them and that Dr Cline, who was affiliated to the extremist Christian sect known as Quiverfull, had been motivated to reproduce as prolifically as possible to meet God's mandate to "be fruitful and multiply".
To him, nothing happens without God allowing it. The seven were appalled in 2017 when, despite the evidence against him, Dr Cline was merely fined $500. At that time, there was no law against fertility fraud. He could be tried only for obstructing the course of justice by denying what he'd done.
Dr Cline begged Jacoba not to persist in making a case against him as it would destroy his 57-year marriage. He said: "You're telling the world and the world doesn't need to know." But she plugged ahead regardless. The documentary shows how hard she had to fight to bring the situation to light, which she eventually did, thanks to Fox reporter Angela Gavote.
Interviews and re-enactments are cleverly interwoven, some using the actual offspring and others using actors representing them.
Fertility treatment has been a legal and ethical minefield in the past, and may still be in some parts of the world. Likewise, women's reproductive rights. This excellent documentary illustrates many aspects of those two topical areas and will lead to some lively discussion. Highly recommended.
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