Noting the GEDCOM note on this profile, I though I would highlight how the Wescombes got to Australia.
John, being Thomas's father, has this note on the profile as seen here: John Wes[t]combe {Australian Immigrant}
"John Westcombe arrived in South Australia (Holdfast Bay) on 12.10.1838 aboard the sailing ship 'Pestonjee Bomanjee' from London (Blackwall) on 28.5.1838 & Plymouth on 11.6.1838."