Two more of Gina Rinehart's children were revealed yesterday as parties in a mystery legal action against her, raising speculation of yet another messy family battle over the late Lang Hancock's legacy.
Mrs Rinehart's daughter Bianca and son John have joined their half-sister Hope in taking their mother to the NSW Supreme Court.
It means that only her daughter Ginia, described as the one closest to Mrs Rinehart, is not a party to the legal proceedings, fuelling conjecture that the dispute could centre on succession within the family's business empire.
But details of the latest family feud surrounding Australia's richest person have been suppressed by the court at Mrs Rinehart's request.
Yesterday, Justice Paul Brereton agreed to the interim suppression order until Tuesday, when he will make a final decision on whether the matter should remain confidential.
Mrs Rinehart is known to be fiercely protective of her family's privacy and has avoided public stoushes. Despite the family's wealth, few details about them are known outside their immediate social circles.
Mrs Rinehart has two children, Bianca and John, from her first marriage to Englishman Greg Hayward and two, Hope and Ginia, widely believed to be twins but born about 18 months apart, from her second marriage to American lawyer Frank Rinehart.
Hope Rinehart Welker, who turned 26 last month, has two children with American-born, London-educated husband Ryan Welker. He has been taken into the fold and in December last year was appointed non-executive director to the board of Mineral Resources, in which Hancock Prospecting and Mrs Rinehart have a small stake.
Mr Welker lists his address as a $5.4 million waterfront home in Sydney, which is owned by 150 Investments.
Mrs Rinehart Welker is a co-director of 150 Investments with her mother and Bianca.
Bianca, 31, originally viewed as Mrs Rinehart's most likely successor, moved to Darwin to start a family and remains a director in Hancock Prospecting, although she appears to have no major role.
John, who changed his surname to Hancock by deed poll eight years ago and vowed to leave Australia amid a family split over his late grandfather's business empire, is understood to have reconciled with his mother and now lives in Thailand. While Lang Hancock and his wife Rose were often in the spotlight, his daughter, Gina, has been famously private and rarely comments publicly.
Hope and Ginia were educated at St Hilda's Anglican School for Girls. Ginia is believed to be studying for an MBA in London.