Helen Fuller, a grandmother of 10 and former primary school teacher, was sitting on a Metro train opposite a white woman about her age and a brown man in his mid-20s when she found herself listening in to their conversation. "I'm blessed with good hearing," she says. She heard the story of how the young man and his family had arrived in Australia from Afghanistan. "He looked a very lovely boy," she says. "I could tell from his face."

When the young man – Abuzar Mazoori, a part-time student and youth worker – said that he had not seen anything of Australia but Melbourne, Helen had what she calls an inspiration. "Sometimes I have these impulses to trust people." Leaning forward, she apologised for listening but said she had a holiday house in Rye and perhaps the young man and his family might like to go down and have a week's holiday there over Christmas. Says Abuzar, "Automatically, there were negative thoughts in my mind – why this person offer me her house?"

Moss and Helen Fuller with Abuzar Mazoori. Credit:Martin Flanagan

For her part, Helen received "a fair bit of negativity" when she told others what she had done. "I was told I was taking a risk. I said, 'People do it for money'." She was supported, however, by her husband, Moss, whom she met at teachers' college in Ballarat 51 years ago. Moss says, "She rules the roost. If she thought it was OK, I did too. I trust her judgment." Moss tells me he remembers Abuzar's name because it sounds the same as "a boozer", another word for pub in his youth, and for that matter, mine.

In another part of Melbourne, Abuzar was encountering similar problems. His brother laughed at him when he recounted the story. "My brother said, 'How is this possible? How she trust you? How you trust her?'." Their mother was confronted by the idea of occupying another woman's home, particularly when that woman was a stranger. "She said, 'I don't know what is in the house. What might happen?'."