The cause of the controversy is the "Ashley Treatment" - a course of surgery and hormone supplements devised for her at her parents' request and with the blessing of doctors - that will for ever keep her small. It involves surgical operations, including a hysterectomy, and hormone prescriptions that will, in effect, freeze-frame her body at its current size
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She was diagnosed, they explain, with brain damage with unknown causes just after birth and has remained at the same developmental level since about three months. Three years ago she began to show early signs of puberty, and they grew anxious about the impact of fertility and of her rapidly increasing size and weight on the quality of her life. In discussions with doctors at Seattle Children's hospital they devised the treatment: removal of Ashley's uterus to prevent fertility, excision of early buds on her chest so that she would not develop breasts, and medication with high doses of oestrogen to limit her growth by prematurely fusing the growth plates of her bones.
http://www.guardian.co.uk/usa/story/0,,1982370,00.html
http://ashleytreatment.spaces.live.com/