"If it helps with you being from Oz, I can guess with some certainty that you are descended from criminals, possibly Celtic criminals!"
'Fraid not; Only New South Wales (Sydney) was a Penal Colony 18th Cent.. South Australia wasn't settled 'til many years after the Penal era, early 19th Cent. My dad's ancestors immigrated from Wales or Cornwall to work the Moonta copper mines, my mum's family as Protestant missionaries. South Australia takes pride in being a Free Settlement. We still delight in teasing Sydney's (now) "aristocracy"; ("What did your family do again?").