Hi Diana
I have not come across a Simon Corlett in the files as yet. I am uncertain about any of the Australian Corlett's, as my husband's family immigrated to NZ and not to Australia. We immigrated from NZ to Australia in the 1980's and as far as I know the only ones from our particular branch to be living in Australia at present, but most likely other younger ones from the other side branches would have come here. There is a good Australian mailing list via rootsweb that you could join and post your message, I am sure someone might know the answer for you or know of the particular family of Margaret and Richard Steele.
All the best
Ailsa