BARNES. Henry and Nehemiah 1851 Ontario Canada

[adrianbarnes]

I need HELP, please!
Greetings all!  I reside in Australia. My Gt Gt Grandfather Henry Barnes was married in Victoria AUS in 1872 and died in Victoria AUS in 1879.
He and his brother Nehemiah were believed to arrived in AUS about 1854. Shipping records being vague I cannot verify this.
Their parents were John Barnes, a carpenter and Ann Brown, both of London (presumably the UK London).
That family does not appear on any UK census or other records.
Whilst searching for Barnes in London, Canada, I have located a group (family?) of Barnes on the Canadian 1851 census at Walpole, Haldimand County, Ontario, including a Henry and a Nehemiah, both about the correct ages.
If they are my Henry and Nehemiah I need to verify how/when they got to Canada and how/when they got to Australia.
Can anyone offer some suggestions, please?
Cheers, Adrian