The parents of conjoined twins, who died less than a month after being born, insisted yesterday that they were right to go ahead with the birth.

Faith Williams died on Christmas Day in London’s Great Ormond Street Hospital, 23 days after being separated from her sister Hope during a mammoth operation.

The twins’ mother Laura Williams, aged 18, was the UK’s youngest mother of conjoined twins and she and husband Aled refused to consider a termination despite doctors warning the babies might not survive.

Mrs Williams told the Mail on Sunday: “Even after everything that’s happened, I still think we were right. They didn’t die inside me like the first doctor I saw said they would. They got this far.

“If I had to do it all again, I would. I don’t really know how to explain how hard it’s been but I still wouldn’t change anything.”

Mr Williams, 28, added: “You make choices in life and we made a choice to give them life.

“We knew the risks but we gave them a chance and so did everyone who has helped us, from the doctors and nurses to our friends and family who have been such a support.

“I feel upset in one way but in another I don’t, because they’re both back together again, the way they were at the beginning. It’s good that she’s back with her sister.”

Faith and Hope were born on November 26. They were joined from the breastbone to the top of the navel and had a shared liver but separate hearts. Hope failed to survive the initial operation to separate her from Faith because her lungs were too small to support her breathing. Faith died from progressive organ failure.

Their parents, from Shrewsbury, Shropshire, who already have a daughter Carly, maintained a virtual constant vigil at the newborns’ bedsides.

Mr Williams said they knew the end was coming when they were called in by doctors on Christmas morning.

“Everything they’d been telling us from the last three days up to Christmas was that she was going down and down and down,” he said. “It was her way of saying she just could not take it any more.”

Great Ormond Street, where the surgery on Faith and Hope was carried out, is the most experienced centre in Europe for separating conjoined twins.