It doesn't do for an Australian to dig around the roots of his family tree if he is afraid of what might be unearthed.
When my paternal grandparents, H. F. Smith and Amelia Skelson were married, the bride's father was recorded as Samuel Skelson, miller. Since the wedding took place in 1890, the assumption might be that, like my maternal great-grandparents, they arrived during the great migration boom in the middle of the nineteenth century. But assumptions can be - well - presumptuous. It turned out that my grandmother never actually knew her father, as she was the daughter of his (relative) old age, and she was still only a baby when he died.