London - A conjoined twin, whose sister died after separation surgery 23 days ago, has also died in a children's hospital in London, Great Ormond Street Hospital said Friday.

Faith Williams died on Christmas Day, 23 days after the death of her sister Hope following surgery to separate them on December 2.

The twins were joined at the chest when they were born on November 26.

Their 18-year-old mother, Laura Williams, became the youngest woman in Britain to give birth to conjoined twins.

She and her husband, Aled, were at Faith's bedside when she died.

"We were always clear that Faith was very sick. She required the full range of skills of our intensive care staff, and underwent a number of further procedures. However, she succumbed to the complexities of her condition," a hospital spokesman said Friday. (dpa)