MWO Tan's booming voice was heard throughout the march-in, as she commanded the 3,000 participants in 29 contingents, while Chia helped conceptualise the musical and directed the cast.
Whether or not the series of firsts was a coincidence, it mirrors the amount of progress that Singapore women have made over the decades.
In 1957, only 26.1 per cent of women worked. Now, about 56.5 per cent of women are in the workforce. Women are also taking up more key leadership roles in the private sector and in the Government.
For example, four women police officers have held the senior position of Police Land Division Commander in the past 13 years.
There are currently six land divisions in the Singapore Police Force, namely Central, Clementi, Tanglin, Ang Mo Kio, Bedok and Jurong. Assistant Commissioner of Police Florence Chua is currently in charge of the Jurong Police Division.
As for MWO Tan, she said she was "honoured to be the first female RSM" but reiterated that she faced the same challenges as her male predecessors.
Still, she acknowledged that it would have been tougher if she or any other woman had taken on the role in the past, saying that "it would have been a great challenge for females to take on a combat role and command the men" then.
"But now, in society, people are open to women taking on high appointments."
Chia echoed MWO Tan's sentiments and pointed out that capability - not gender - counts these days.
She said that her gender might have mattered at the beginning, but "after the first few seconds, you sort of throw that out the window and everybody gets down to work".
Ms Nicole Tan, president of women's group Aware, said: "There have definitely been many improvements, although we would like to see a faster pace of change in terms of more women achieving leadership positions."
She believes that, as women make up half of Singapore's population, fair representation is important to ensure diversity of experiences and views. Nonetheless, MWO Tan's role in this year's parade is a landmark.
Her disarming personality makes her popular with the children in the contingents.
She said: "As you can see, all the children are very close to me. As I walk past, you see they like to stick to me. They look upon me as a mother figure." She is a mother of three sons, twins aged 21 and another who is 19.
Chia said the musical, which is told through the eyes of a mother and son, has received positive feedback that it packs a more emotional connection. She said her role as creative director was intertwined with her personal role as a parent.
Like any working mother, she juggles her career and family.
She said, half in jest: "I'm a mother of an extremely hyperactive four-year-old, Sol, who, at this point, is not talking to me because he has not seen me for quite a few months."
She is quick to add that there are perks to being the parade's creative director.
She said: "My son's still happy as he gets to see the parade and the rehearsals on Saturdays. He loves the tanks, the fighter jets, the helicopters.
"So I think my credit rating in his eyes is quite high."
MS CLARISSA TAN, 29
Customer-service officer at a manufacturing company
NDP leadership role: Red Cross first-aid volunteer team leader
Why she volunteers for the Red Cross: For the past decade, Ms Tan, a former kidney patient, has been a first-aider at every National Day Parade (NDP) and rehearsal, except for the one last year.
The youngest of three children, she had a kidney transplant on Christmas Day in 2009, and was still recuperating months later.