Like most sisters, Tiny and Fenny Sio share many things. They fit into the same-sized clothes and shoes. They share toiletries and facial products. They have similar tastes in Hong Kong drama serials and Hollywood blockbusters like the recent space drama Gravity.
But, five months ago, the sisters took sharing to a new level.
Fenny, 30, the younger sibling, donated one of her kidneys to Tiny, who is five years older.
Today, both sisters are healthy. Along with Tiny's eight-year-old daughter Charlotte, they will take part in this year's OCBC Cycle Singapore event to raise awareness of, and money for, kidney transplants.
Tiny, 35, an administrative assistant in her husband's photography company, knows just how lucky she is. Both of her kidneys had severely deteriorated in the course of two years.
Had her sister not volunteered to donate one of her organs, she faced an uncertain future with four-hour dialysis sessions three times a week for the rest of her life.
The average waiting time for a kidney transplant in Singapore is nine years, with more than 400 patients in a queue on a medical register. There are more patients than there are kidneys available and between 15 and 20 people die here each year while waiting for a transplant.
When Tiny first found out that she needed a kidney transplant two years ago, her husband Alex Siew, 33, father Suleman, 66, mother Ivanna, 61, Fenny and younger brother Jackson Robin, 27, all volunteered to donate a kidney.
Recalling how she felt, Tiny said: "If I was able to get a new kidney, I would have been happy. But it's not something you can force. "I was speechless and very touched. I know this kind of support doesn't happen in all families."
After tests, it was found that Fenny, a prisons officer who is single, was the most suitable candidate. Naturally, when it was time to make a decision, she had many conflicting emotions.
For the eight months leading up to the operation, she mulled over the decision at length and quietly convinced herself that she was making the right choice.
"There was a lot of fear and hesitation, a lot of niggling stuff, like worms eating me up on the inside," said Fenny. "Initially, I tried to ask myself if I felt that it was my duty to save my sister. I wondered what if my other kidney fails?
"Even now, when I think about it, my hands become clammy," added Fenny, as tears welled up in her eyes.
Sensing her sister's uneasiness, Tiny, seated across the table, reached out to offer a comforting hand.
But in the end, the thought of seeing her sister go through constant dialysis was enough to convince Fenny to go for surgery.
Said Fenny : "I wanted to see her healthy. I could not imagine seeing her in needles, going through the dialysis process.
"The image was disturbing, because the blood vessels become swollen and bruised. I know my sister is very vain. She would have been heartbroken to see her skin like that.
"Also, if my niece saw her mum going through this, she would have been very sad."
Fenny has to refrain from participating in high-impact sports, like her favourite wakeboarding. She has also given up on one item on her bucket list - skiing in the Swiss Alps.
But, while there are some things that have to be sacrificed, there are also benefits. Adding to their obvious emotional attachment, the sisters now share a heightened biological bond.
Said Tiny: "Recently, we keep teasing each other because it's like we have a sort of telepathy - one day she was moody at work, and for no reason, I was moody too.
"I told her, maybe it's because a small part of you is in me now."