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- O'Neill
- O'Olaf
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Rhanullt b. c 1020
- O'Reilly
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Bernard J. b. 16 Jan 1937, d. 3 Apr 2000Bernard Joseph b. 7 Nov 1876, d. Jan 1935Bernard Joseph b. 17 Mar 1904, d. 18 Jul 1955James b. 11 Feb 1894Margaret b. c 1920
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Donncuan b. c 1030Gillacaemphin b. c 1005, d. 1056Gillachomhghaill b. c 980, d. 1041Gillachomhghaill b. c 1055More b. c 1114, d. 1191Murcertac b. c 1089
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Clyde Everett Jr. b. 20 Jun 1920Hannah b. Nov 1859, d. c 1901
- Oakley
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Richard Alfred b. 14 Dec 1913, d. 23 Jun 1962
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Daisy b. 19 Aug 1891, d. 15 Aug 1961
- Oatman
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Martha Elizabeth b. 10 Dec 1866, d. 1 Oct 1936
- Oberlin
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George Dewey b. 7 Jun 1898, d. 28 Mar 1995Henry A. b. Jan 1861, d. 1936
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Anna Katharina d. a 1817
- Ochsenbein
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Alice Mary b. 28 Jan 1914, d. 11 Sep 2008
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Bernice Ella b. 11 Jan 1882, d. 20 May 1973Hattie Francis b. 4 Sep 1891, d. 29 Mar 1911
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Arley Belle b. 1 May 1900, d. 26 Apr 1932William Clair Charles b. 1864, d. 3 Dec 1928
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Eva b. Oct 1879, d. 1922Joseph Thomas b. c 1834Susan b. Feb 1863, d. 23 Nov 1932