A 10-year-old KwaZulu-Natal girl's latest bout of illness may have strengthened her Jehovah's Witness parents' court battle against receiving blood transfusions.

In responding papers to the Durban High Court, the child's father said a private hospital had been willing to administer an alternative treatment to their child when doctors learned that the family's religious beliefs did not allow blood transfusions.

The family is are among three sets of parents who are fighting a court order granted to KwaZulu-Natal health MEC Sibongiseni Dhlomo and two doctors to administer blood transfusions to their children aged three, five and 10.

The five-year-old boy and three-year-old girl suffer from sickle cell anaemia while the 10-year-old girl, from Nquthu in northern KwaZulu-Natal, has severe anaemia - the underlying cause has not yet been established.

In his affidavit presented to court on Tuesday, the father said his daughter became ill during a family holiday in December and was admitted to Netcare Mulbarton.