The Family Court has approved the sterilisation of an 11-year-old girl.

Family Court judge Paul Cronin found that the performance of a hysterectomy on the child, identified only as Angela, was "in the child's best interests".

Angela has Rett syndrome, making her profoundly disabled and unable to talk or use sign language.

The court, sitting in Brisbane, heard that Angela acted in a similar way to a three-month-old baby.

She has to be fed and cared for and has no bladder control.