Up to three million Britons may be wrong about who their real father is, experts claim. But using DNA paternity tests to discover the truth can cause its own problems.
When Tessa found out she was pregnant after fertility treatment, she felt a mix of delight and doubt.
Dad's got blue eyes, Baby brown...
This wasn't simply pre-baby nerves - she suspected that her husband might not be the father. For Tessa had started sleeping with a colleague when the stress of the ongoing treatment became too much.
Keen to build a family with her husband, she let him believe the baby was his. But her lover threatened to reveal all if she ended the affair, and Tessa soon fell pregnant again. This time, her lover started to make nuisance calls to her home.
Tessa had no choice but to tell her husband. "I said to him, 'I've had an affair and you may not be the father of my children.' So with that, he went up the stairs, got dressed and left. And that was it," Tessa says in Women Who Live a Lie, a programme for the BBC's Five Live Report.
After a paternity test determined that her husband hadn't fathered either child, he broke off all contact.
"I kept this a secret because I thought that my worst nightmare would come true, that the family would be split. Which it has been," Tessa says. Her children, now five and six, never see the man they first knew as "Dad".
One of many
Tessa is far from alone in trying to keep this painful secret - and advances in DNA testing mean women may find it more difficult to maintain the lie.
Estimates suggest that 5% of the population may have a different father to the one they think they are related to, says Professor John Burn, of the Institute of Human Genetics in Newcastle.
Relate counsellor Paula Hart says honesty is the best policy
"People lie because they feel it best but there will be serious repercussions"
She draws parallels to children of sperm donors, who have the right to know the father's identity under human rights law
He runs one of the UK's few paternity testing services, which carries out about 300 DNA tests a year - a third of results surprise those involved. But men should be cautious about trying to prove their suspicions, he says, for the truth is often unkind.
"There is a genuine Pandora's Box in these sort of tests, that once you've opened the lid, you cannot close it again; once you know this, you cannot unknow it. You must ask yourself, 'if the result goes the way I'm not expecting, can I cope with that?'
"To be suddenly told - or to have a child told - that the person they thought was a parent isn't can have profound implications on their perception of who they are. And if people have an established family relationship, these tests can sever it forever."
Truth will out
For years Angela lived in fear of just such fallout. For her youngest daughter Sally, now 17, is the product of an affair she had for several years. Angela told no-one but two close friends, and felt so guilty her marriage eventually broke down.
"I knew the day had to come some time to tell my daughter, but I wrapped it away in cotton wool thinking not this year, not next year, maybe the year after. I was frightened I'd lose all three of my daughters," Angela told Five Live Report.
Last month, her oldest friend finally snapped and insisted Sally had a right to know who her real father was.
Many lie to "protect" their family
So Angela sat her youngest daughter down for a serious chat. "My heart was bursting out of my chest - I thought that this was the moment in time that I'd going to lose her. I was sobbing when I told her that a long time ago I'd had an affair, that I'd got pregnant and that she was the best mistake that I'd ever made."
Sally took it well (at first - now she is beginning to show she is quite disturbed by the news), so Angela decided to tell her ex-husband - who reacted calmly - and her old lover, who agreed to see Sally when she's ready.
"I'm relieved, but my relief has hurt a lot of people," Angela says, her voice catching as she recalls how her eldest daughter branded her a slut.
"But my main concern is for my children. I hope they're strong enough and wise enough to know that people make mistakes, but they don't have to pay for it the rest of their lives."
The Women Who Live A Lie will be broadcast in the UK on BBC Radio Five Live on Sunday 18 May in the Julian Worricker programme from 1000 BST and again at 1835 BST.
The man I thought was my father and whose name I am proud to have today died when I was 9. I have a much loved stepfather. When I was 18 I was told that my real father is also still alive. Certainly this won't be discussed until after my grandparents die as it might hurt them. I don't judge my mother as I don't believe she has done any more wrong than any of us do in our complicated lives. She worried about telling me for 18 years. I wouldn't exist without this rather complicated story, so how can I regret it?
For three years I raised a child - from birth - as my own. I was her Daddy. She was my daughter. Then I discovered that her mother was having an affair; soon after came the bombshell: she's not my daughter. Now, two years on, I am divorced. I am no longer allowed to refer to 'my child'; I am no longer recognised as a father. I have tried to retain a continuing relationship with the child of my marriage: but to no avail. There is no legal recognition of my status. Her biological parents want me out of her life, and there is nothing I can do.
My mother told me on my 15th birthday that my 'real' father was someone I knew as a friend of the family. Actually it wasn't a complete surprise as children have a sixth sense about the way people behave with each other. It is now 35 years later and my biological father is dead, but STILL only my mother and me know the truth. The whole secretive experience has made it very much more difficult for me to form close and emotionally trusting relationships with women.
I am white, and married to a half-Sri Lankan gentleman. Our first boy was white, blue-eyed and blond. The second was to all intents and purposes Indian. Most people assumed they had different fathers - I got the cold shoulder from other parents on the school run, and gossiped about by social workers. It's only now that Paul and I have been together for 25 years, people are starting to realise we're an item and the boys are both ours.
I can't condone the breaking of a trust, but fortunately not all situations end in the destruction of a family. A friend found that his daughter of three was not biologically his own, and while it put a strain on the relationship between him and his partner for a time, he put enough value on their relationship and family to want to stay together. It's been four years now, and not succumbing to pride and anger has left all three of them in a loving, happy family.
I have a friend who found out by accident the man she considered her Dad is nothing of the sort. This led not only to a break up of the family but also an argumentative relationship with her mother, whom she will never forgive for hiding her true parentage from her. She also knows her Dad is not her father - but he doesn't. She still sees him, and her biological father, but due to the way in which she found out she will never reconcile with her mother.
I'm a divorce lawyer and deal on a daily basis with the fall-out of adultery (the term 'affair' makes it sound glamorous which it almost never is) and other manifestations of selfish behaviour by spouses/partners. The devastation that this breach of trust causes to everyone involved, especially the children, has to be experienced to be believed. There is always an excuse, some justification for this unacceptable behaviour, but ultimately it always boils down to an inability to put other people before oneself.
Mark Page, UK
Women should think strongly about withholding back the truth as to who their children's real father are. Obviously this is done for personal reasons as it could upset family units. But what about the medical implications this could have on their children later in life? Do they not have a right to know who their biological father is and if they have any hereditary medical history they should be aware of?
Tania Bradley, England
There is of course a way of avoiding all this heartache and deceit. This is for paternity tests to be conducted routinely on every newborn child. On each birth certificate would be written both the biological father (which will never change) and the social father (which may well change more than once throughout the life of the child). This system would bring transparency and confidence to all.
Roger Thomas, Wales
There is of course another way of avoiding all this heartache and deceit. Remain faithful.
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