I have a Margaret Corlett b 1832 dau of Simon and Ann (nee: Skeally). Margaret married Richard Steel in 1857 and it is said that she wished to migrate to Australia to follow a relative there. Richard and Margaret migrated to Australia in 1857, arriving 1858.
Although I don't have a Robert Corlett in my research to date, there is a Patrick Cowley mentioned in Margaret's Grandfather's (Simon Corlett) will in 1808. Do you think there might be a connection?
I can send you more details if you are interested

Diana