"Is this normal?" What happens when family members reunite and fall in love.

In 1979, at 42, Barbara Gonyo was reunited with her son, Mitch, 26 years after giving him up for adoption.

She immediately felt a maternal love for her son, she wrote in her memoir, but those feelings soon developed into a deep affection that manifested in sexual fantasies about him. Yes – Barbara felt a sexual attraction towards her son.

She expressed her sexual desires to him, but he did not reciprocate the feelings.

Barbara was convinced that her attraction was not abnormal. So, she coined the term Genetic Sexual Attraction (GSA), to explain the powerful sexual feelings that can happen when biologically related adults are reunited late in life.

As she argues in her book I’m His Mother But He’s Not My Son, sexual attraction between relatives may be a byproduct of “missed bonding” that would have normally taken place between family members had they not been separated.

According to The Guardian, GSA is more common than you might expect. In fact, “50 per cent reunions between siblings, or parents and offspring, separated at birth result in obsessive emotions,” the publication reported in 2003.

17 years on from that data, it is evidently still a feeling experienced by long-lost family members today.

In 2015, The Cut published an interview with an 18-year-old woman, who at the time was preparing to marry her biological father.

The anonymous teenager explained her father emailed her mum asking to see his daughter when she was 15. She agreed, and at 17 she was reunited with her father, after 12-years of estrangement.

“We chitchatted online for a few days and found out we were similar,” the girl explained to the publication. “We shared the same favourite TV shows — The Simpsons and The Big Bang Theory — and we both love to draw. He came to see me about a week later. You wouldn’t have believed we hadn’t been around each other for 12 years. The idea of “getting to know him” seemed strange because we are so much alike.”

The girl admitted that she found her father attractive, and added she was confused by those feelings. After staying with him for five days, she realised she was romantically attracted to her father, who had a girlfriend at the time.

But during her stay with him, she discovered the feeling was mutual.

"We discussed whether it was wrong and then we kissed. And then we made out, and then we made love for the first time. That was when I lost my virginity."

Asked if she felt coerced, she responded: "Absolutely not."

The two entered a romantic relationship, became engaged, and moved to New Jersey where adult incest is not illegal. They plan to have children together.

Theirs is not the only story of blood relatives, separated at birth, who later find each other and fall in love.

A woman named Meg spoke to ABC's Earshot podcast about her experience of GSA with her half-brother.

Meg, who was in her late 20s and married when she met her half-brother, remembers feeling "crazy, head over heels love" for him.

"Why does it feel like I'm attracted to you?" she remembers thinking. "This is weird, but it won't stop. It won't go away, and it just escalated from there."

The half-brother, experiencing the same feeling, brought up their confusing, mutual attraction. When they kissed, Meg tearfully explained she felt such a forceful attraction for him that she didn't think she could stop.

They frantically googled what their attraction meant, saying they both questioned "Is this normal?". They were inundated with responses from people who were going through the same thing.

Their attraction only intensified, and Meg discovered she was pregnant. The father was her half-brother - not her husband, leading to their divorce. Today, Meg no longer has any contact with her half-brother or her husband.

Although the above stories may surprise you, there could be a scientific or sociological basis for sexual attraction between relatives who meet in adulthood for the first time.

GSA might be explained by the ‘Westermarck’ effect — named after sociologist Edward Westermarck — which holds that people living in close domestic proximity during the early years of life are desensitised to sexual attraction.

Furthermore, a 2011 University of Illinois study published in the Personality and Social Psychology Bulletin found that people appear to be drawn to others who resemble their kin or themselves — with those findings leading psychologist RC Fraley to speculate: “It is possible [that] as Freud suggested, incest taboos exist to counter this primitive tendency.”

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