Two women only realised they had been given to the wrong mothers 55 years after they were switched at birth in an NHS hospital.
The women were born in the West Midlands in 1967, and were taken to the nursery, where it was standard for newborns to sleep at this time in order for mothers to rest.
But when they were returned, the were mixed up and only realised after at-home DNAs returned surprising results decades later.
In BBC documentary The Gift, the families spoke about the devastating fallout, with one daughter telling how she always felt like an imposter growing up and one mother telling how her daughter no longer calls her mum.
The two women, named Jessica and Claire in the documentary, though these are not their real names, are now in line for compensation from the NHS, with the amount not yet disclosed.
Such errors are vanishingly rare: In 2017, the NHS said in response to a Freedom of Information request that it had no record of it happening.
But the advent of easy DNA tests revealed this was at least one case where it happened, and NHS Resolution has now accepted legal liability for the appalling error.
The situation was unique and complex, it told the BBC.
The mistake was discovered with home DNA tests (Stock picture: Getty)
Newborn babies being cared for in a ward in London 1967. At this time, babies were given paper ID bracelets (Picture: Getty)The mistake was revealed when Claire, as well as Jessicas brother Tony, both took DNA tests, which revealed they were biological siblings.
Confused by the result, they spoke to one another about what might have led to it which revealed the connection with the same hospital.
Newborns in the UK are now given radio frequency identification (RFID) tags immediately, which allow their location to be tracked, meaning babies being accidentally switched is now extremely unlikely.
But before the 1980s, wards relied on handwritten tags, which left much more room for error.
Clare had been surprised by her own results, which showed no biological link to those she had thought were her relatives, and a cousin listed she did not know.
While Tony was worried by his results and fearful of upsetting his mother, now in her 80s, Claire felt more as if the results had explained something about her relationship with her family: There were no similarities, in looks or traits [] I thought, yes – I’m adopted.
She and Tony discussed what best to do, with Tony saying he would take her lead with whether she wanted to progress this at all.
Claire was eager to meet her biological family, and was very emotional to meet her birth mother and feel as though they had always known each other.
She found it hard to discuss her own childhood, which she described as very difficult being raised in absolute poverty, homelessness, often went hungry, and all that entails.
Breaking the news to the mother who brought her up, who died earlier this year, was the hardest thing she ever faced, though she reassured them nothing would change her feelings towards her.
Jessicas mother, Joan, told the BBC she was delighted to reunite with Claire and feel she had gained a daughter.
But the story was less happy for Jessica, who declined to be interviewed for the documentary and no longer calls Joan mum.
Joan said: It doesnt make any difference to me that Jessica isnt my biological daughter. Shes still my daughter and she always will be.
Claire said she now intends to the make as much as she can of time with her birth family, but knows it will never be enough as the time she should have spent was taken away.
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