A woman reported her parents to the police after discovering they are brother and sister.
Donna Price said that her childhood was normal and happy, and to the outside world they looked like the perfect family.
But one day in 2014 her world began to fall apart when she discovered that her parents were siblings.
She says the revelation tore the family apart, and the case ended up in court last month where the pair pleaded guilty to incest but avoided jail.
Speaking to The Sun, Ms Price, 32, said: "I feel my childhood was all based on a lie. I hate them.
"There's not enough words to describe how much I hate them." During the police investigation it was found that the man she thought was her father was not her biological dad – a DNA test discovered that her mother conceived during an affair with an unknown male. Her three younger siblings, however, were found to be the pair's biological children.
Her discovery happened in December 2014 when an estranged aunt revealed the news, after she initially dismissed rumours as someone trying to "stir up stuff".
She said she felt "sick", but held fire and gathered information before going to the police. A two-year investigation began, and the pair eventually pleaded guilty in court.
They both received suspended sentences.
Her dad, Robin Price, was contacted by the paper and admitted the relationship was wrong. But he said he did not meet his partner – his half-sister – until adulthood and by the time they discovered the family connection they'd already fallen in love.
"I suppose, looking back on it, we shouldn't have done it." They separated in 1994, but stayed in contact to help raise their son Steven, who was diagnosed with severe epilepsy.
The Sexual Offences Act 2003 makes it illegal in England and Wales to have sex with an adult who is closely related, including a parent, sibling, and aunt or uncle. Different legislation is in place in Scotland and Northern Ireland but the restrictions remain similar.
In 2011 a 47-year-old man pleaded guilty to incest, after beginning a sexual relationship with his daughter after they were estranged for several years.
In 2014, a mother and son revealed they had become involved in a romantic relationship - 30 years after giving him up for adoption.