Law Of Direct Paternity
The likelihood that a man is the father of a woman's child is directly propotional to how much she likes him.
Riffing off the Law of Inverse Fertility, this is the rule that when a woman has multiple romantic partners and becomes pregnant, the father will be the man who is more likeable or with whom she is truly in love. Sometimes justified by making the other partner gay, impotent, or otherwise "unable to perform". Overlaps a lot with Your Son All Along. See also Who's Your Daddy?.
- In The Pillars of the Earth, Aliena has sex with Jack once, and gets pregnant by him, despite her marriage to Alfred. In fairness, she has sex with Jack before the wedding, and Alfred is impotent the entire time they are together.[[hottip:*:It's implied that this is because of the "curse" laid on him by Ellen, though whether it's the direct effect of the curse or its psychological effects that make him impotent is left ambiguous.]] Notably, she also gets raped by William, but doesn't end up conceiving as a result of that.
- In the American film The Postman, a woman has sex with the title character because her husband is sterile and unable to impregnate her. Later, her husband is killed and she is taken as a sex slave. Fortunately her captor is unable to perform, meaning that the child she ends up having is definitely the hero's.
- In Braveheart, Isabella conceives a child by William Wallace after a single rendez-vous with him. It's implied that she's been unable to conceive by her husband, the prince, because he is gay.
- A lot of women on Jerry Springer think this is the truth.
- The same goes for Maury.
- Averted in Mamma Mia!. Sophie invites the three men who might be her father to her wedding. Her mother is in love with Sam, but which man is actually Sophie's father is never revealed in story, as Sophie ends up deciding she doesn't care. (Word of God says the father is Bill.)
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