Mrs Gervaise is now in the UK with her husband Hilton, re-establishing the family bonds broken when she was "stolen" aged just four.

"The whole story is really quite incredible," the Gervaises' daughter Mercedez told the Illawarra Mercury.

READ MORE: ACM Spring Cash Code winner Melissa Wightman plans to spend her $10,000 prize helping her mum and taking a holiday

The Gervaises, who are responsible for the Fresh Start Trailer which provides support to the homeless in Wollongong and beyond, have had their roots in Bellambi for 20 years.

It was a volunteer at the trailer who quite unwittingly sparked the reunion.

"A volunteer and my mum ended talking about adoption and somehow that lady broke down a wall," Mercedez said.

"My dad had always wanted for her to look for her family but she was in fear of what she would find.

"She always said if she was loved, her family would've found her."

Little did Mrs Gervaise know that for more than 50 years her family on the other side of the world had been doing just that.

It all began in Pontefract, West Yorkshire when Susan's mum, a single woman with six other children, agreed for neighbours to take the-then four-year-old on a fortnight's holiday to Florida.

In 1969 in England, with parental permission and a birth certificate, a child could travel internationally.

The couple did not go to Florida but rather fled to Canada. Over the ensuing years they moved to Australia and later New Zealand, raising Susan as their own, telling her they had adopted her.

"They were travellers and by all accounts she had a wonderful childhood," Mercedez said.

"But she grew up believing her mum abandoned her which is why she was adopted."

It was when Susan attempted to get her own passport as a 16-year-old and needed her father's signature that he came clean, explaining she was not adopted and that he and his late wife never intended taking her back to the UK.

READ MORE: RSPCA recommends reward-based training to instill good behaviour

Eventually Susan returned to Australia as a 19-year-old and made her life here, marrying Hilton Gervaise, settling down and going on to have three kids.

"As a family we've been back and forth to England over the years, but never to Pontefract," Mercedez, the couple's first-born, said.

As it turns out, all but one of Mrs Gervaise's siblings still live in the historic market town.

And while it may have been 1:30am in Australia, just an hour after that fateful Facebook post in July, Mrs Gervaise spoke with one of her sisters.

"There was a lot of crying," Mercedez said, "and total disbelief."

Since then, with her husband and two sons, Mrs Gervaise travelled to the UK and reconnected with her biological family, although sadly, her mother died eight years ago.

And only now has she learnt how her family tried for decades to find her.

"But she'd had so many names, and lived in so many places there was no chance her real family could ever track her down," Mercedez said.

"As far as we know the police weren't ever involved but there were all sorts of missing person appeals over the years in England."

And after all those years Mrs Gervaise got to celebrate her 57th birthday at the local pub with four of her six her siblings.

She'll return home later this month safe in the knowledge she was loved and missed for every one of those birthdays.

"It's the start of another chapter for her," Mercedez said