SINGAPORE - Five-year old Grace Tan has an infectious smile. She goes to school and sometimes likes to go for a swim.
She can stand on her own two feet. But that is about all she is able to do.
Grace was born with Pyruvate Dehydrogenase Complex Deficiency (PDCD), an extremely rare condition that delays mental and physical growth. Her behaviour and movements are like those of a one-year-old.
There are only three diagnosed PDCD cases in Singapore and about 500 cases worldwide.
When Grace was diagnosed with the condition at 10 months, a genetics doctor told her parents not to expect much and to be prepared to take care of her for life.
Her parents, Mr Alex Tan, 44, an IT consultant, and Mrs Mary Tan, 45, who also works in the IT industry, did their own research and found that children with PDCD usually do not live past three years old.
Grace is turning six this year, and her condition has improved tremendously over the past few months.
Her parents attribute it to her strict "ketogenic diet" - a high-fat, low-carbohydrate diet used primarily to treat children with epilepsy.
Besides going to a special school twice a week, she goes for swims and has physiotherapy sessions, acupuncture treatments, and occupational therapy or speech therapy sessions.
Although she still cannot walk or talk, she has learnt to stand on her own - an achievement that makes her parents optimistic about her development.
"I really hope she can start to walk this year," says Mr Tan.
Every little improvement - such as making vocal sounds and standing - means a lot to her parents.
Their simple wish is that Grace will one day say "Mama" and "Papa", and walk on her own.
Saturday was World Rare Disease Day. It is an annual observance to raise awareness of rare diseases and improve access to treatments.
It also aims to improve medical representation for individuals with rare and genetic diseases and their families.
I photographed the family early last year and last month, and saw how Grace was improving as well as the challenges her family faces daily taking care of a child with special needs.
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