O'Sullivan, still coming to terms with the loss of his vivacious daughter, said Lisa's life was immersed in the horse industry.
"She was always a good horsewoman and understood horses," she said.
This included working for her champion horse trainer father when she finished a Business Management degree at Waikato University and working at her husband's family thoroughbred stud..
O'Sullivan told the Herald on Sunday he suspected his daughter knew something was wrong well before she went to the doctor following the National Yearling Sales at Karaka last year.
"Looking back she had completely changed the house and painted her kids rooms as if she knew what was going to happen."
He said the cancer diagnosis, delivered after Lisa complained of being unwell at the sales, floored the family.
"The news at that stage was horrendous.
"They gave her just three months to live."
She underwent treatment and lived a further 16 months, including a late bid to beat the condition with an experimental treatment in America.
Unfortunately, she had an unusual form of leukemia and was unable to be cured, he said.
He said she would be sadly missed by many people.
"She was extremely vivacious and full of fun.
"She not long ago turned 44 and had her whole life ahead of her and her life of her kids and that's where we've all got to be behind them."
He thanked the many friends and family who supported his daughter through the final months, reserving special praise for his son-in-law who tried everything he could to save her.
"What he did was unbelievable really. Whatever he says, he can't say 'if only'."
A service will be held at the Matamata stud this Friday.