The White Australia policy treated her father as a "foreigner and enemy" and resulted in her mother's citizenship being revoked.

But despite that, in 1945 — at the age of just 18 — Kathleen Quan Mane enlisted as a decoder in Australia's Air Force for what would be the final year of World War II.

Ms Quan Mane and her sister Doreen, the youngest of five girls in their family, were among the first 21 Chinese-Australian servicewomen to join the war effort.

Ms Quan Mane served as a cypher for the Australian military in WWII. ( Supplied: Chinese ANZACs )

The now 91-year-old war veteran was born in Sydney to an Australian-born Chinese mother and a Cantonese father who came to Australia in the early 1900s.

She recalled although her parents had been very proud and supportive of her and her sister joining the Defence Force, her father had never been allowed to become an Australian citizen.

"During WWII, he was classed as a foreigner and enemy," Ms Quan Mane said.

"Mum was born in an Australian country town.

"When she married dad, her Australian citizenship was taken away from her. She was classed as a foreigner [and] had to report to the police station every so often."

Under the White Australia policy, anyone who was not substantially of European descent was barred from becoming a citizen.

Ms Quan Mane's mother had her Australian citizenship taken away when she married. ( Supplied: Kathleen Quan Mane )

But despite suffering under Australia's discriminatory policies and racism, many of Ms Quan Mane's family members have gone on to serve in the military.

"Each of my [other three] sisters either had a son or husband in the defence force," she said.

"Our family was what you could call a military family. That was quite unusual, because Chinese girls usually did not leave home before getting married."

A very secret job and a special bond

It was not until World War II that Australian women were allowed to join the Defence Force, with more than 66,000 women enlisting.

Founded in 1941, the Women's Auxiliary Australian Air Force (WAAAF) was the largest of the nation's World War II women's services.

When she turned 18, Ms Quan Mane enlisted and became a cypher in the WAAAF where her sister had served as a clark general for more than three years.

Being a cypher was a very secret job, and until recently was classified under national security legislation.

As decoders, these women translated confidential messages from military code into English using codebooks, and vice versa.

"That's why it was so secretive, because of troop movements, personnel movements, generals' movements — all secret," Ms Quan Mane said.

Ms Quan Mane describes her time as a codebreaker in WWII as "extraordinary". ( ABC News: Samuel Yang )

On the home front, barriers and prejudices were breaking down between servicewomen, as Ms Quan Mane bonded with other Australian girls serving in the Air Force in what she described as an extraordinary year.

"I came from a family of Chinese on both sides," she said.

"We spoke Chinese in the home, Cantonese, we ate Chinese food, we lived the Chinese lifestyle, and going into the forces was a great change for us.

"Although we played with the kids next door, they were Aussies, real ocker, we [learned] the Australian way of life from them, but it was very limited.

"Going into the service I was a bit apprehensive first, but the girls were very nice — neither my sister nor I encountered any racism. That was a big step forward too."

Records from the Chinese Museum in Melbourne show more than 600 Chinese-Australian men and women enlisted during World War II.

From humanitarian work to a family reunion

After the surrender of Imperial Japan, Ms Quan Mane and her sister devoted themselves to the United Nations Relief and Rehabilitation Administration (UNRRA), doing humanitarian work in China.

Ms Quan Mane shows photos of her time with the Defence Force to her niece Kaylene Poon. ( ABC News: Samuel Yang )

Three decades later, in 1979, she returned to Australia and reunited with her family.

She was appointed as honorary secretary of the WAAAF WA branch until its closure in 2016.

Her niece, Kaylene Poon, is now a local history researcher in Perth who is trying to preserve the little-known stories of Chinese-Australian veterans.

Ms Poon said she was proud of her aunt.

"You think of the Anzacs, you think of a golden-haired Australian person, you don't see them of a different colour or background, she said.

"It's nice to know now that they have been recognised."