Patti included a black and white photograph of her parents from their wedding day. Patti's mother wears a beautiful white gown, while her father is dressed in a traditional sailing uniform.
Patti's followers were quick to praise the gorgeous pic.
"You look so much like your mum," one wrote, while another added, "Beautiful photo Patti. I’m sure they are looking down on you all bursting with pride 😊"
A third echoed, "What a wonderful photo to treasure xx Enjoy the day I'm sure your parents are watching over you and your family!"
Earlier this year Patti opened up about a "family secret" she had discovered.
After years of being kept in the dark, the beloved Aussie entertainment legend has learned her family was once the subject of a grisly infant murder investigation, dating back several generations.
Patti discovered the disturbing death probe while shooting for the upcoming SBS season of Who Do You Think You Are? – a series where celebrities search their ancestry.
Investigators told the grandmother-of-three that the death of an infant baby, related to her father’s side of the family, was the subject of an intense, high-profile media storm and criminal trial.
This bombshell revelation caused Patti to break down and ‘dissolve into tears’ – horrified that her family harboured such deep, dark secrets for so long.
"I had no idea it would be so dramatic," she told The Daily Telegraph. "Every time someone would mention the series before I did it, they’d say “I wonder what they’ll find?” And I’d say, “Oh, they’ll probably find a murderer and I’ll die.” And they did."
While details on the baby murder are sketchy at this stage, it has reportedly caused a great deal of heartbreak for the devoted mum and grandmother.