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I located some records of your family. The first record is the 1900 marriage record for Martin Hanley and Margaret Ryan. Martin's father is shown as Thomas. I located the 1901 census record for Martin and Maggie on Princes St. Your grandfather Robert was born in October 1909. I also located the 1911 census record which shows Martin, Margaret and their five children living with Patrick Condon and his wife Mary Ellen. The census record indicates that Martin was a son to Patrick Condon. Was he actually a step son?
Did Robert Hanley marry Margaret Kiely or did he marry in England?https://civilrecords.irishgenealogy.ie/churchrecords/images/marriage_returns/marriages_1929/09068/5280710.pdf