gina rinehart called ` the fat ' and ` fatty ' by son john hancock in emails .
` fat would have quickly grown tired of supporting your shopping , ' he said .
nearly a decade later , the siblings are united in a bitter trust dispute .
bianca rinehart gave evidence in the dispute into the family 's finances .
ms rinehart was forced to sign contracts , and left ` distressed and crying '
children of gina rinehart lodged case to increase stake in family company .
siblings currently control just 23 per cent of family 's hancock prospecting .
gina rinehart has a stake of more than 76 per cent in the company .