As an undergraduate, Ms Wang, now 25, decided to spend some free time volunteering at the children's ward of a hospital as a balloon sculptor.
But by the end of her second visit, she realised that there was more she could do to help.
"I noticed that children with chronic illnesses were treated more as patients, less as kids," she says.
"They did not get much of a childhood, which was a shame. "The problem, she observed, was that the adults did not have the right tools to communicate with these children. She saw that there were many scared children, who feared medical procedures such as getting their blood drawn. And she also noticed that parents wanted to help pacify the children, but sometimes did not know the right words or the best way to ease their worries and explain why these procedures were necessary.
"So I decided to use my design skills to do good by making medical procedures less traumatising for these children," Ms Wang says. And so Rabbit Ray was born - a cuddly rabbit toy that can be opened up to reveal miniature versions of the tools that doctors use to draw blood from a patient. "He's basically a friend to help explain to a child what blood-taking will be like," Ms Wang says. "It even comes with a needle that you can use to draw blood from the toy."
While there are online videos out there that do help to explain to children what blood-taking is all about, Ms Wang says the effect is not the same. "You can't hug an iPad. It's not as comforting as hugging a toy."
She then worked with the National University Hospital (NUH) to develop the first Rabbit Ray prototype, which she submitted as her final-year project at university.
"User feedback was easy to obtain - I'd been working with children since I was 18, so I could talk to them easily," she adds. Ms Wang has since sold Rabbit Ray sets to various medical institutions in Singapore.
However, she soon realised that this was an unsustainable business model as each hospital would only buy five to 10 sets and would hold on to them for many years. So she got to work developing a new version of Rabbit Ray that parents can buy and use at home.
It is still in the design stages, but Ms Wang plans to launch these home-friendly Rabbit Ray sets for sale to the mass market by the end of the year and is already taking pre-orders on her website, joytingle.com.
These sets will include a Rabbit Ray hand puppet, a bag of miniature tools, a story book and a plush toy in the shape of a red blood cell.
Rabbit Ray aside, Ms Wang has also begun pursuing another source of revenue - commissioned projects. Medical institutions can approach Joytingle to create products "with empathy for children in mind".
The firm has worked with KK Hospital's emergency department and NUH's paediatric oncology nurses to create various products aimed at helping kids understand the medical procedures they have to undergo.
For KK Hospital, Joytingle produced a three-minute animation using kid-friendly language to explain why some wounds need stitching and how it is performed.
"The emergency ward, as you know, is a fast-paced environment that sees a high turnover of patients," Ms Wang says. "So the product had to be something that could relay the information quickly. We thought a video would be a better medium than a toy."
Up to 300 children now watch the video every week, she adds. "Nurses also save time - they often have to assure anxious parents and explain technical jargon but they usually don't have the time since this is an emergency department. "But this cartoon explains everything to the patients while they wait for their turn to see the doctor."
This is only the beginning, Ms Wang says. The company, which is already in the black, plans to sell Rabbit Ray sets across South-east Asia. Ms Wang also hopes to expand her team - she is the only full-time staff at Joytingle, and she needs people with graphic design, animation or sewing skills to join her.
She is also interested in hearing from survivors of chronic illnesses or people who have had close relatives who battled with illnesses to give her ideas about how else children can be helped through such situations.
"Children are not just small adults. You can't talk down to them. It's really a different language that you need in order to reach out to them."