Heard of cri du chat?
Neither had Jesse Petersen, until seven years ago.
Just after her daughter Vayla was born, Ms Petersen, 25, was told her precious new arrival had the syndrome, sometimes called "cry of the cat".
Sufferers have a chromosome missing and display similar characteristics to people with the more common Down syndrome.
It affects about 1 in 35,000 to 1 in 50,000 people and is one of about 7000 rare diseases spotlighted by the New Zealand Organisation for Rare Disorders' annual awareness day.
Vayla goes to primary school now on Waiheke Island, but her mother and stepfather still need to take a hands-on role with her.
Vayla's speech is largely limited to "mama" and her beloved "ball". She needs to be fed through a tube and at school she has a teacher aide at her side.
The "cry of the cat" name comes from the distinctive noise people with cri du chat, or 5p- syndrome, sometimes make.
Ms Petersen said Vayla's cat-like cry had subsided as she got older but she had it at birth.
"Now I know her cry was so different. I was very young when I had her so it was just a beautiful sound to me then.
"It was quite shocking being told that your daughter has a disorder you've never heard about."
Communication is instead through sound and sign language, both the official New Zealand version and a simplified one called makaton.
"Mostly I understand her through sounds and picture and her body language," Ms Petersen said.
"Not many people can understand her. It's just family and close friends. She tried very hard to get things across."
Ms Petersen said Rare Diseases Day yesterday was about raising awareness of the many little known and understood conditions people have.
A lot of medical professionals weren't even familiar with cri du chat and Ms Petersen still remembers the old-fashioned language used when it was broken to her that her daughter would have "severe mental retardation".
Vayla has another rare condition, bronchiectasis, which damages the lungs' ability to clear mucus and raises the risk of infection.
"Just seeing your child really sick is just really hard," Ms Petersen said.
She works part-time as a teacher aide and, since becoming a mother, has completed a Bachelor of Disability Studies.
All of that has seen her become somewhat of a walking educator.
"What's good about having Rare Diseases Day or any awareness day is people get to understand that there are so many people out there that have differences."
NZ Organisation for Rare Disorders chief executive Letitia O'Dwyer said a rare disorder or disease was something that 1 in 2000 or more people had and most were genetic.
• If everyone with a rare disease (350 million) lived in one country, it would be the world's third-most populous.
• About half of people with rare diseases or disorders are children.
• Thirty per cent of children with a rare condition won't live to see their fifth birthday.