Singapore celebrates its 48th birthday on Aug 9, and to tie in with this, The Straits Times Photo Desk has put together 48 Singaporean Seconds, an audio-visual tribute to Singaporeans who have made this little red dot their home.

We are releasing their stories and videos in the next few weeks. In the 18th instalment of our series, we talk to Sister Linda Sim.

Linda Sim, 58, mission awareness coordinator

When Sister Linda Sim was growing up, all she wanted to do was serve the nation.

In the 1970s, she applied to the Singapore Armed Forces to be a front-line soldier, but was told women could take up only clerical positions. The Singapore Police Force also turned her down as she was too petite.

Undeterred, the gutsy woman took up taekwondo and eventually earned a black belt. Then she heard her religious calling.

"If I couldn't serve in the army, then I will serve in God's army," quipped the 58-year-old Franciscan religious sister.

She ran a Catholic hospital in Zimbabwe for three years, and spent 17 years in England as a religious trainee and trainer before coming home in 2004.

She now works as a mission awareness coordinator at the Mount Alvernia Hospital and Assisi Hospice. On weekends, however, she swops her religious robes for a taekwondo dobok.

She teaches martial arts to kids who are in remission from severe illnesses in a class sponsored by the Singapore Taekwondo Federation.

She has also represented Singapore overseas and has won medals at numerous competitions, including a silver medal in the Korea Open International Championships in July.

"I thought I was too old. But I got the chance to represent Singapore and wear the flag on my uniform," she says proudly.

- Photos and videos by The Straits Times Picture Desk