The 22-year-old economics graduate, who left Zimbabwe in 2004 to study at Perth's Murdoch University, knew not to ask her father about political matters.
"I asked him how he was and he said, 'We're still with this old man', meaning Mugabe and the fighting. That's as much as he can say."
The Movement for Democratic Change leader talks to his daughter long-distance every few days, even after he was detained last week, for the fifth time in about 10 days, by thugs working for President Robert Mugabe.
With violence escalating as the June 27 presidential election runoff approaches, Ms Tsvangirai said she tried to keep conversations with her father upbeat, telling him about her first job as a salary packaging consultant with a Perth firm. "And I try to encourage him. I'm a Christian so I read him quotes from the Bible."
This weekend, the reticent daughter (one of six Tsvangirai children) will appear for the first time at a public rally in Perth to support a free and fair Zimbabwean election.
"I came to a point where I said to myself that the time was right to speak out about my dad, the MDC and (the plight of) everyone in Zimbabwe." She said more aid was needed for Zimbabweans suffering extreme food shortages and homelessness.
She will also call on the Australian Government to put further pressure on African leaders to speak out against the Mugabe regime. "They should be told not just to watch what's happening, but do something about it."
The Tsvangirai family is scattered on three continents - son Garikai, 27, lives in Canada while another daughter, Vimbai, 25, lives in Sydney and works for the Sydney City Council. Mr Tsvangirai's wife, Susan, has spent the past two months in South Africa with twins Millicent and Vincent, 14, and 30-year-old son Edwin, after threats escalated against her husband.
"I do believe there will come a time when we can all go back to Zimbabwe and my father will be president." And she said if he won next week's poll, "I'll be on the next flight home".
A spokesperson for the Department of Foreign Affairs and Trade confirmed yesterday that it was investigating reports that at least three adult children of pro-Mugabe leaders in Zimbabwe's despotic regime were studying or working in Australia.
He said the Government would continue to review the visas of Zimbabwean children whose parents appear on an international sanctions list. In August, eight children of Mugabe government figures - all students studying in Australia - were deported.
Ms Tsvangirai said she believed people would understand why her mother and siblings were all living outside Zimbabwe.
"Any father who was in my father's position would do the same to ensure their children were safe. Any parent would do that. I'd say my father is very brave, a loving dad and a humble man," she said.