The earliest we have been able to locate our Walter Todman in Australia is 1890 when he applies for a patent for shearing equipment which was duly reported in "The Sydney Mail and New South Wales Advertiser"(i) on the 27 December 1890 So I was very excited when I found an advertisement in a newspaper column for MISSING FRIENDS

"Willoughby, or Todman (James), left Millwall in 1884; last letter from Sydney, N.S.W., in 1888. Mother asks." (2)

Family legend states that Walter changed his name from Willoughby to Todman. The only marriage that my cousins and I have been able to fine between a Willoughby and a Todman occurred in 1854 when Charles Willoughby married Mary Ann Ramsey Todman in Gillingham Kent. They had a son James Lincoln Willoughby. On Walter's marriage certificate his mother was Mary Ann Willoughby, although the father was listed as Walter Todman(iii).

So now I am seeking to make contact with anyone who might be able to shed light on the mystery.

References
(i) "Patent Office Transactions" The Sydney Mail and New South Wales Advertiser, 27 December 1890, p. 1446, col. 3; digital images, TROVE (http://nla.gov.au/nla.news-article163648327 : accessed 18 Oct 2015), The Sydney Mail and New South Wales Advertiser (NSW : 1871 - 1912).
(ii) MISSING FRIENDS. (1901, April 13). Evening Journal (Adelaide, SA : 1869 - 1912), p. 6. Retrieved October 21, 2015, from http://nla.gov.au/nla.news-article207944213
(lll) Registry of Birth, Death and Marriages, Victoria, "Certificate of Marriage Walter Todman & Martha Ellis 16 January 1892 Reference# 345" (Original certificate the in family papers of Myrtle Sharp.)