The BBC has spent months trying to establish what happened with Beth and Laura.
During our investigation, we found two other British families who had been treated by Firdevs and were also suspicious the wrong donors had been used during their IVF treatments.
They too have completed commercial DNA tests which indicate their suspicions were correct.
Beth and Laura question whether their clinic even ordered donor Finn’s sperm.
When we contacted Firdevs she said she had not been responsible for ordering sperm at Dogus and said no information about the request for donor Finn had been passed on to her.
She also cast doubt on the reliability of Beth and Laura’s commercial DNA test. It is not possible to conclude “with certainty” that the wrong donor was used, she says.
Firdevs has also told the BBC she “did not perform IVF treatment” between 2011 and 2014, when Beth and Laura were patients, despite there having been detailed descriptions on Dogus’s own website of procedures that she offered during that time.
Dogus clinic, which Firdevs says was responsible for Beth and Laura’s treatment, has not responded to our request for comment.
By 2015, Firdevs and Hodson had left Dogus and were working together at another clinic in Northern Cyprus.
Hodson, who no longer works in the territory, has not replied to the BBC’s questions about whether she passed on the sperm order to Firdevs.
Beth, Laura and the children have now done further, accredited DNA tests which can be used in British courts. These have confirmed James and Kate are not biologically related and were not conceived from the same sperm donor.
A leading forensic genetics expert, who has analysed all the family’s tests, told us it is unlikely that either child is biologically related to donor Finn.