Thomas, my husband's O'Brien/Dwyer line is a little earlier than yours, but this is what we have.
Thomas O'Brien was born to Thomas O'Brien and Mary Ryan about 1814 at Glassdrum, Cappawhite, Tipperary. His parents were married at Anacarthy, Co Tipperary on 3 February 1813.
Thomas, born 1814, married in 1853 at Knockavilla, Tipperary to Ellen (or Eleanora) Dwyer (O'Dwyer). Ellen was the daughter of Patrick and Johanna Dwyer. Patrick's occupation was a cooper.
In 1862 Thomas and Ellen and children Bridget 8 years and Johanna 5 years sailed on the Ship "Theresa" for Australia. Family lore says Thomas was a widower prior to his marriage to Ellen. Also it has been written that Ellen wanted to come to her brothers in Australia. Regards Denise