Surviving conjoined twin Faith Williams has undergone surgery to improve her circulation.

The two-week-old little girl, born to Laura and Aled Williams, of Harlescott, Shrewsbury, underwent the surgery at London’s Great Ormond Street yesterday. 

She was today described as critical but stable. Faith’s sister Hope died just hours after surgeons carried out a complicated operation to separate them last week. Her lungs were not strong enough to keep her alive alone.

Hayley Dodman, spokeswoman for the hospital, said: “Faith Williams had surgery yesterday to assist with her circulation.   

“The aim was to ensure more blood flows to her body and less through her lungs. She is currently critical but stable.  

“Laura and Aled Williams would like to thank all the staff involved in Faith’s surgery yesterday, and those who continue to offer her high levels of care at the hospital.”

Medical experts gave her a 50/50 chance of survival but she has continued to improve and was considered strong enough to undergo further surgery.

Mum Laura, 18, made medical history by becoming the youngest ever woman to give birth to conjoined twins.

Professor Agostino Pierro, head of the surgical team at Great Ormond Street Hospital, said the separation surgery was “one of the most complex and challenging operations” ever faced by staff at the hospital.

The girls were delivered by Caesarean section at London’s University College Hospital on November 26 with a combined weight of 4.8kg. 

They were then taken to Great Ormond Street – the most experienced centre in Europe for separating conjoined twins.

Medical staff at the Royal Shrewsbury Hospital warned Laura and her husband Aled, 28, a binman who used to work for Veolia in Shropshire, that their babies might not survive after a 12-week scan revealed the problem but they refused to consider a termination.