Looking for Sweeney of Tipperary Ireland

John Sweeney was born in Tipperary (don't know which parish/town)in about 1842 to Edward Sweeney and Margaret Brennan. He emigrated to New South Wales and married Maria Crowley in Mudgee then had 3 sons - Edward, John Patrick and Jeremiah. John Sweeney was acidentally killed by a dray in 1972 at the age of 30. I have no way of tracing his Irish ancestry without a parish or town and no knowledge of his siblings, so hope someone can help. Thanks.