Lady Susan, who has been raising awareness about ovarian cancer since her diagnosis, acquired her title during her third marriage to Sir Frank in 1985.
The New Zealand financier broke records for the highest-price paid for a Sydney property in 1988 when he bought "Paradis sur Mer" at Point Piper, an affluent harbourside suburb in the city's east, from Lady Susan's second husband, British gambling tycoon Robert Sangster.
Lady Susan came to public attention as the wife of rising Liberal star Andrew Peacock and with their three daughters, the glamour couple were often referred to as Australia's John and Jackie Kennedy.
She went on to marry British horse-racing millionaire Robert Sangster and then New Zealand tycoon Sir Frank Renouf.
An advocate of the arts, horse racing and, she often laughed, helping to prop up the champagne industry, Lady Susan has been working to raise awareness of ovarian cancer.