John Bjelke-Petersen said his mum was a formidable force who raised him and his three sisters while also supporting her husband's political career.

"They didn't have electoral offices back in those days. Dad would get mum to come in and sit down and dad would dictate what he wanted to say. Mum would take shorthand and then type it up and dad would have a speech in a matter of half-an-hour," he said.

"Everybody, as you travel round, the first question was how mum was. It was a sign that through being the wife of premier and then as a senator what sort of impact she had made on people."

One of Lady Flo's final wishes was for her controversial husband's tarnished political reputation to be restored, after he was dumped as leader by the Nationals in 1987 amid a corruption scandal following almost 20 years in office.

He faced corruption allegations stemming from the Fitzgerald Royal Commission. In 1991, the 80-year-old was charged with perjury arising from his evidence to the inquiry, but a jury was unable to reach a verdict.