Gina Rinehart is Australia's richest person with an estimated wealth of $20Billion. Ms Rinehart was born Georgina Hope Hancock in Western Australia in 1954 - the only daughter of Hope Margaret Nicholas and mining magnate Lang Hancock. She pulled out of Sydney University after a year of studying economics and joined the family business. Over the years she honed her knowledge of the Pilbara iron-ore industry, and when her father died in 1992 she became the head of the family company. Following the death of her father in March 1992, Rinehart became Executive Chairman of Hancock Prospecting Pty Limited plus the Group of companies. All companies within the group are privately owned. Gina Rinehart, a mining industry billionaire, had acquired 12.8 per cent of the nation's second-largest newspaper company by February. She first appeared on the Business Review Weekly rich list in 1992 and has been on the list every year since, becoming a billionaire in 2006. She has also attracted media attention because of her strained relationship with three of her four children. Ms Rinehart has four children from two marriages. She married Englishman Greg Milton when she was 19 and the couple had two children, John Langley and Bianca Hope, but divorced in 1981.Two years later she married American lawyer Frank Rinehart. They had two children together, Ginia and Hope, before Frank Rinehart died in 1990.Last year Hope Rinehart Walker, Bianca Rinehart and John Hancock commenced legal action against Ms Rinehart, seeking to have her removed as a trustee in a multi-billion-dollar family trust .Ms Rinehart's youngest daughter, Ginia, sided with her mother and is a defendant in the case.