While she was still alive, Madam Chua Ah Lek took pains to teach her only child about what she called life's "waves" - about staying upright and upbeat, no matter how overwhelming the currents seemed.

She died of kidney failure in 2011 aged 65, but would have been comforted to know that her advice has seen Mr Jason Chee through some of the harshest tests imaginable.

Through a naval ship accident in 2012 that robbed the navy serviceman of both legs, his left arm and three fingers on his right hand, and cancer that led to the removal of his right eye in May, the wisdom of his late mother has been his source of strength.

The 34-year-old, a national para-table tennis player, was diagnosed with choroidal melanoma (a cancer of the eye) after a tumour was found in his right eye in late April. He told The Sunday Times: "She taught me to be an upright, positive person - to be determined and to not give up on things and what I plan to achieve.

"She told me that (the outcome of) obstacles can be good or bad - but I have to face all of them. Even if I cannot get past the obstacles, it's all right. Just go for the next one. She taught me not to fear anything."

Doted upon by his parents - father Chee Kwok Chor, 75, was a vegetable seller before retiring in 2011 - he feels an odd sense of comfort that his mother did not live to see him go through the trials of the last five years. "I think it would have broken her heart," he said.

But he also knows she would have been deeply consoled by how he has responded to each ordeal.

He said: "I've achieved many things that she wanted me to."

Madam Chua had always hoped he would seek a tertiary education. Mr Chee began pursuing a degree in mathematics after her death, and is into his third year at the Singapore University of Social Sciences.

For someone who had also harboured hopes for her son to be an athlete, she would also have been gratified to know that he is a successful para-paddler. Mr Chee has multiple medals from the 2013 and 2015 Asean Para Games, winning a team gold and an individual silver in 2015, and will compete at the next edition in Kuala Lumpur next month.

Above all, she would probably have been proudest to see him living out her teachings every day.

A self-proclaimed optimist who has served in the navy for 13 years, Mr Chee says he tells himself to stay calm before steadily navigating his way past every obstacle.

This is perhaps why he did not cry after his accident in 2012, nor were there any tears when he was forced to part with half his vision.

The last time he broke down was at his mother's funeral. His affection for her, and the role that she continues to play in his life, is clear.

Unemotional while speaking about his journey over the last five years, it is only when he reminisced about her that he broke into a smile.

He recalled: "I have many fond memories of my mother. In my highs and lows, she has always been there for me."

Mother and son used to observe a simple ritual before each school examination or competition - a visit to the temple, usually Tse Toh Aum in Sin Ming Drive to pray for safety and well-being.

He would also often accompany his mother, whom he remembers as a capable home cook, to the wet market. Such trips would usually be followed by him standing next to her in the kitchen with a notebook in hand, conscientiously jotting down the ingredients and steps for cooking various dishes.

He said: "My mother loved home-cooked food and when I was a kid, I always wanted to learn cooking from her. At first, she wanted me to get out of the kitchen because it was dirty, but I insisted."

Today, he counts chicken curry and sweet and sour pork as his best dishes.

Closing his eyes and taking a moment before he continued, he said: "I always tell myself that my late mother is still around. She is watching what I do. When I play table tennis, I can feel her beside me telling me what to do. When I'm cooking, I can feel her beside me teaching me what ingredients to put into a delicious meal.

"I can feel her still around motivating me, telling me not to give up. When I want to do things, I always think of her - I can't disappoint her."

Madam Chua may no longer be alive, but if she were, this is what her only child would say to her.

Said Mr Chee: "Mama, it's okay. There's no need to worry. Don't feel sad. I'm still very strong. I can do it, I can overcome these obstacles. Your son will pull through."