While the American Psychological Association does not use the term, GSA is what it sounds like: a phenomenon that occurs when two family members, who were separated early in life, eventually meet and experience an intense sexual attraction to each other — though not all act on it.

What is it called when two siblings are in love?

While cousin marriage is legal in most countries, and avunculate marriage is legal in many, sexual relations between siblings are considered incestuous almost universally. Thus, many cases of sibling incest, including accidental incest, concern siblings who were separated at birth or at a very young age.

What is it called when family members fall in love?

Genetic Sexual Attraction, or GSA as its more commonly known, most frequently occurs when a person has been separated from a biological family member - be it mother, father, brother or sister - from a young age, and upon meeting them again, becomes sexually attracted to them.

Why siblings are not attracted to each other?

According to Westermarck, children growing up in close proximity are not sexually attracted to each other as adults. Quite the contrary: the Westermarck effect meant that overfamiliarity and boredom automatically caused siblings and other close relatives raised together to go out of their way to avoid sexual contact.