His health deteriorated suddenly around 2007 and his family arranged care for him. One of his children took charge of his father's affairs as his "attorney for personal care and welfare", taking oversight of finances and healthcare.
However, in 2012, the businessman instead appointed a lawyer and close confidante whom he had known for 30 years.
The offspring launched legal proceedings to reverse the decision, and hired psychologists to declare the father "mentally incapable", stating in affidavits he wasn't able to look after his finances.
Examples of the father's erratic behaviour were cited in papers filed with the Family Court, such as writing blank cheques to rest-home staff, calling a high-profile politician to seek an emergency loan, and giving $55,000 to an ex-girlfriend.
In 2012, the man's children wanted rest-home staff to confiscate their father's passport to prevent him travelling overseas.
The claims were backed by affidavits filed by another of the man's children and his wife, from whom he was estranged. They blamed his "increasingly erratic and paranoid" behaviour on the lawyer.
He also gifted $97,000 to his ex-wife — and demanded she repay it more than a year later.
The lawyer countered that one of the children had requested a $1m loan to buy a Remuera townhouse at the same time it was being claimed the father was "mentally incapable".
He told the Herald on Sunday that the family dispute "was gradually being unravelled and sorted out". The children did not respond to requests for an interview. The father said it was a private matter and being resolved.