Charities have warned of the rising number of adopted children contacted by their birth parents via Facebook, leading to emotional and psychological distress.
The popularity of social networking websites has seen an increase in breaches of guidelines against unplanned contact with hundreds of adopted children unexpectedly hearing from their natural families.
In the worst cases, some young people taken into care in the 1990s have seen relationships with their adoptive families completely break down after hearing from their biological parents.
One teenage brother and sister ran away from their homes after their natural mother got in touch with them on Facebook. They are now living with her, hundreds of miles from their childhood home, according to the Times.
Another teenage girl took to drinking and smoking after her life with her adoptive family was disrupted by her birth relatives.
“Unplanned and unsupported communication, contact and reunions between adoptive and birth families via Facebook and other social networking sites has already had a dramatic effect on adoption,” said Jonathan Pearce, chief executive of Adoption UK.
“This will only increase in the future and will mean a radical rethink of how we arrange and support adoptions from care.”
A childhood trauma expert joined the debate and said social networking sites could “blow adoption out of the water”, making it more likely that children will be in contact with their birth parents before they are 18.
Helen Oakwater, who wrote Bubble Wrapped Children, said one of her three adopted children had been contacted via Facebook by her birth mother just before Christmas two years ago.
“Children are never told the truth about their past,” she said. “They get a sugar-coated version of it, typically that their mummy couldn’t look after them very well, but she was a very nice person.
“They’re not told that they were left for days on end in their cot or buggy, unfed and unchanged, while their parents took drugs, or of the scale of physical or sexual abuse they may have suffered.
“They need to be told the truth gradually as they get older, and even see the evidence. It is usually the case that the parent will deny any maltreatment and tell their child they have been lied to.”
Last year, the British Association for Adoption & Fostering warned the internet was making it easy for young people to trace their natural parents and other relatives, by searching for their names or photos.
David Holmes, chief executive of BAAF said: “Social media is here to stay – we cannot put the genie back in the bottle. We need to learn how to deal with it in relation to contact issues with birth families.
“We strongly urge adoptive parents to familiarise themselves with social media, so they are able to talk to their children with confidence about all the issues.”
A Facebook spokesman said: “Protecting the people who use Facebook has always been our top priority. We provide a safe and more trusted online environment by design, offering people industry-leading tools to control what they share and with whom they share it.
“These controls help protect children and parents involved in adoption from unwanted contact online. We encourage adoptive and foster parents and children to adjust their privacy settings to control who can contact them on Facebook. These settings allow you to control who can send you messages and friend requests, who can see photos and personal.”