SINGAPORE - Five-year-old Grace Tan was born with a metabolic disorder called Pyruvate Dehydrogenase Complex Deficiency (PDCD), an extremely rare condition that delays mental and physical growth.
Though she is turning six this year, her behaviour and movements are like those of a one-year-old.
She has developmental issues such as slower brain development, difficulty swallowing and weak muscle control.
When Grace was diagnosed with the condition at 10 months, her parents did their own research and found that children with PDCD usually do not live past three years old.
"We decided on the name Grace (as) we felt that she is God's grace to us. At the same, she will really need a lot of God's grace over her life," her mother said.
There are only three diagnosed PDCD cases in Singapore and about 500 cases worldwide.
Straits Times Photojournalist Seah Kwang Peng photographed the family in early 2013 and February 2014, and saw how Grace was improving as well as the challenges her family faces daily taking care of a child with special needs.
Grace takes between one and two hours to fall asleep every night, and tends to wake up and cry whenever she feels any discomfort. Her parents then need to take turns to put her back to bed.
"Many a time she wakes up in the middle of the night at 4am or 5am and cries for one, two hours. She basically wakes up everybody in the house." her mother Mary Tan said.
Things that we take for granted, like being able to pick up a cup to take a sip, Grace needs time to learn, with her parents teaching her patiently step by step.
"My biggest fear for Grace is that what if everything that works well now, stops working for her. So one day what happens if she starts to regress," her mother said.
Grace's parents say they do not know the psychological impact that their younger child's condition has on their older child, Sarah, but tried to make sure both are not deprived of anything they need.
Her parents worry about what will happen to her once they are gone. "My biggest hope is that she will be able to take care of her basic needs by herself, like feeding herself, or taking a bath herself," her father Alex Tan said.
Mr Tan is a freelance IT consultant and works in an office within walking distance from their home. This enables him to check on Grace whenever he can.
The family hardly dines out or travels. They only go for short road trips to Malaysia because of the child's dietary restrictions and the need to bring along appliances required to prepare her meals.
Grace is under a strict ketogenic diet - which is a high-fat, low-carbohydrate diet used primarily to treat children with epilepsy.
Every component of a meal is measured down to the gram and grinded to puree.
Oil is added as her main source of energy rather than carbohydrates.
Her condition has improved tremendously over the past few months. She goes to a special school twice a week. Besides going to school, she goes for swims and has physiotherapy sessions, acupuncture treatments, occupational therapy and speech therapy sessions.
Her parents bring her out to the pool for weekly sessions, but her weak muscles means she sometimes has difficulty lifting her head, and ends up drinking the pool water when she is swimming.
Her parents' simple wish is for her to start walking. "It's something that we have actually planned for her over the last two years," her mother said.
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