Dr Oon Chiew Seng

She spent her whole career at the start of life, then built a home for the end of it — at an age when most people are long retired. There is no finishing line.

We treat retirement like a finishing line.

You cross it, you sit down, you've earned your rest. My own grandparents stopped trying anything new around 70. "We're too old for that now."

I keep thinking about that whenever I read about Dr Oon Chiew Seng.

For more than 40 years, she worked at the very start of life. She was Singapore's first O&G specialist to go into private practice — opened her own clinic on Armenian Street in 1959, solo. No private hospital. No specialist backup. Her only anaesthetist was a British army doctor who left the moment each delivery was done.

She delivered thousands of babies. Decades later, grown adults would still stop her to say thank you. One restaurant owner gave her a free meal on finding out Dr Oon had delivered her.

She retired in 1991. She was 75.

Here's what I didn't know until recently.

Retirement bored her. Travel and mahjong "couldn't fill all her time." So she volunteered at a home for the aged sick — and noticed something that bothered her. People with dementia were being dumped in mental hospitals. Stigmatised. Poorly cared for. Nobody was building anything for them.

So the 77-year-old baby doctor decided to build it herself.

Think about that for a second. Most people at 77 are winding down. She flew to Australia and toured 16 specialist dementia homes to study how it should be done. Took courses. Went to conferences. Then came home and raised $1.8 million to unlock the funding.

In 1999, Apex Harmony Lodge opened in Pasir Ris. Singapore's first purpose-built home for people with dementia. 210 residents.

She chaired it until she was 96.

And here's the part that stays with me. In 2013, Dr Oon was diagnosed with dementia herself — the very condition she'd spent her retirement building a home to care for.

Someone once asked if she'd finally "arrived," satisfied with everything she'd achieved. She said:

"Arrive where? Life is not a race. To me, there is no finishing line."

She spent her career welcoming people into the world. Then she spent her retirement making sure they left it with dignity. She started that second career at an age most of us would call the end.

There was no finishing line. There was just more work worth doing.

What's something you've quietly told yourself you're "too old" to start?