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My great-great grandfather, John Kelly was purportedly from Omagh or Armagh, County Tyrone, Ireland. His date of birth is uncertain, but is thought to be 1839, give or take a few years. His parent's names are unknown. His date of immigration to the United States is also unknown, but we do know that on July 19, 1859, he enlisted in the army (Co. K, 4th Infantry, New York City) for the Union by Lt. Winder. This is the earliest documented evidence we have found for him. It is possible that he had a brother named Patrick Kelly, who joined the same Co. and regiment a day earlier. According to this same enlistment document, Patrick was born around 1836. Can you help me find John's place and date of birth and his parents?