A loving sister is to donate her bone marrow to assist her brother's life-long battle with leukaemia.

Jennifer Armstrong, 14, of Skipton, will have the operation to help her 11-year-old brother Richard who has fought the disease since the age of two.

After a traumatic wait to find a suitable donor, the Skipton Girls' High School pupil was diagnosed as a positive match and the operation is set to take place at St James's Hospital, Leeds, later this month.

The children's father, Andrew Armstong, 48, of Hetton, near Skipton, said: "We are very proud of both of them. Jennifer is just glad she can do something to help her brother."

Richard, who attends Upper Wharfedale School, Thresh-field, near Skipton, has spent much of his young life undergoing chemotherapy.

He underwent two years of treatment from the age of two and just as the family were beginning to think he had fully recovered Richard was diagnosed again in October 1998.

Another two years of gruelling chemotherapy ensued and then early this year doctors discovered more problems with the youngster's blood cells.

"It came as a triple blow," said Mr Armstrong, a father of four. "It is a major upheaval in the whole family life and there are psychological repercussions when you watch someone you love suffering."

Doctors believe the present condition, myelo dysplastic syndrome, could lead to leukaemia and the family are hoping the transplant will eradicate both conditions.

Mr Armstrong, a partner in Armstrongs Solicitors, Otley Street, Skipton, said his son rarely spoke about his health problems and had carried on a normal life while he was not in hospital. "He has been very brave. The operation will leave him in isolation for quite a while and he will be off school for months," he said.

That was why Mr Armstrong contacted Richard's favourite football club about him being a mascot for a game.

The football crazy youngster is a season ticket holder for Bradford City but will be unable to attend games after his operation.

"I just wanted to make him happy and he was thrilled. I particularly want to thank the club for their full support," he said.