Nine-year-old Zecia Chew looks and behaves like any other girl her age, but her health has come at a high price.

Without fortnightly medical treatment that costs $24,000 a month, her liver and spleen would swell up and eventually burst.

Zecia has a rare ailment known as Gaucher disease, where her body does not produce an enzyme needed to get rid of a type of fat.

Without the fortnightly hospital visits for enzyme replacement therapy, the fat would accumulate in Zecia's organs and would eventually prove fatal. To her parents' knowledge, only two other children in Singapore have the same problem.

Her father, Mr Chew Tuck Choy, 38, recalled how the disease caused her to become bloated as a toddler.

"Her stomach was very big, almost like a pregnant baby," said Mr Chew, who works as a bell services supervisor in the hotel industry.

"She was very bloated and uncomfortable and she couldn't balance well, so she kept falling down."

Mr Chew, who has two younger daughters, said that his family receives government assistance that helps to pay for the bulk of Zecia's medication.

The family forks out several hundred dollars each month.

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Their monthly household income is about $6,000 a month before Central Provident Fund deductions.

Even so, Mr Chew has depleted his Medisave account twice and that of his wife once - amounting to around $30,000 altogether - to pay for his daughter's medical treatments.

The Chews live comfortably, although they do not have much to spare as most of their savings goes towards Zecia's treatment.

This is a concern for Mr Chew, whose father and father-in-law both have health issues.

As Zecia grows taller and heavier, she will also need a higher dose of the medication she is taking, which raises her treatment costs.

The Chews hope that the government assistance they are getting will continue to be sufficient as Zecia's medical costs rise in the future.

"Basically, we have almost no savings," Mr Chew said.

"But the most important thing is that Zecia is healthy."