Brooke, otherwise known as "the woman who never aged", stayed the same size for 15 years and required 24-hour care from her parents.

BROOKE Greenberg still mystifies doctors, even after her death.

Brooke, otherwise known as "the woman who never aged", stayed the same size for 15 years and required 24-hour care from her parents.

She looked and behaved like a toddler until her last breath.

Her mother, Melanie Greenberg, appeared on Katie Couric's talk show in January of this year, along with Brooke and the rest of her family. She said if another mother with a toddler asked her how old Brooke was, she usually wouldn't answer truthfully.

"My system has always been to turn years into months. So, if someone asked today, I might say, she's [20] months old," Mrs Greenberg said.

"She literally is the fountain of youth if you think about it," her father Howard Greenberg told NBC.

"She's shown me that as hard as it gets sometimes, the next day it can only get better."

Brooke was eventually diagnosed by her physician with "Syndrome X", an unidentifiable and unexplained rare disease - which is known to affect only about six people in the world - where they do not age physically or mentally since early childhood.

"While the outside world may have noticed Brooke's physical stature and been puzzled by her unique development state, she brought joy and love to her family," Rabbi Andrew Busch, who delivered the eulogy at the funeral, told the New York Daily News.

"Her parents, three sisters and extended family showered her with love and respected her dignity throughout her entire life."

Brooke and her family appeared on Katie Couric's talk show in the US in January.

They said Brooke could not talk, had baby teeth and still had to be pushed about in a chair.

"From age one to four, Brooke changed. She got a little bit bigger. But age four, four to five, she stopped," her father told Couric.

Brooke was born a month premature, weighing 1.814kg. She needed surgery for an anterior hip dislocation but it was only when her younger sister aged beyond her that her parents realised something was amiss.

They took her to specialist after specialist who were unable to diagnose her condition.

Dr Eric Schadt, director of Icahn Institute for Genomics and Multiscale Biology at New York's Mount Sinai Medical Centre, said that Brooke had "no apparent abnormalities in her endocrine system, no gross chromosomal abnormalities, or any of the other disruptions known to occur in humans that can cause developmental issues."

Her parents bought a casket and clothes for her funeral after being told repeatedly that Brooke was going to die.

"The older she gets, the more unbelievable it gets," her mother, Melanie Greenberg, told TV station WBAL in 2005.

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