Searching for Atkinson Family

Am seeking, any and all, information on my 3rd great-grandparents and their family . . . especially seeking verification of their births and immigration. Also, the parents of Robert Atkinson . . . John Atkinson and Elizabeth Marshall. THANK YOU!

Robert ATKINSON, son of John ATKINSON and Elizabeth MARSHALL was born on 10 Sep 1791 in Armagh, Northern Ireland (Annamoy, Eglish Parish). He died on 12 Aug 1862 in Platte City, Andrew, Missouri, USA. He married Margaret FERGUSON on 17 Jul 1819 in Armagh, Northern Ireland (Eglish Parish; Church of Ireland; Blackwatertown). She was born about 1797 in Armagh, Northern Ireland. She died on 25 Jan 1881 in Platte City, Andrew, Missouri, USA.

Obituary: Mrs. Margaret Atkinson came from Ireland to this country in 1844, and located in Andrew County, Missouri. She was about 84 years old, was a member of the Episcopal Church from her youth till she came to this country, at which time she attached herself to the M.E. Church, and remained a member of that church till her death. She died in great peace, and was sensible to the last. Only a few moments before she died she spoke to her daughter and family in her usual tone of voice, and said she was willing and ready to die. She departed this life on the morning of the 25th of January, at 8 o'clock.  (As printed in the Savannah Reporter, Missouri, USA, on February 4, 1881) 

Robert ATKINSON and Margaret FERGUSON had the following children:

JOHN ATKINSON was born on 15 Mar 1821 in Armagh, Northern Ireland. He died on 16 Apr 1901 in Whatcom, Washington, USA. He never married

Robert R. (Randolph?) ATKINSON, was born on 06 June 1827 in Eglish Parish, Armagh, Northern Ireland. He died on 16 October 1891 in Yamhill, Oregon, USA. He married Elizabeth CLEMMENS, daughter of Anthony Cook CLEMMENS and Sarah JOBE on 14 March 1850 in Andrew, Missouri, USA. At the age of 7, Robert R. Atkinson, emigrated to U.S. from Ireland, settling with his parents in Missouri.

MARGARET ATKINSON was born on 30 Jun 1834 in Armagh, Northern Ireland. She died on 15 Feb 1911 in Bolckow, Andrew, Missouri, USA. She married Joseph MONTGOMERY, son of John MONTGOMERY and Eve KECK on 12 May 1859 in Andrew, Missouri, USA. He was born on 23 Jul 1830 in Wheeling, Marshall, West Virginia, USA. He died on 05 Mar 1895 in Bolckow, Andrew, Missouri, USA. 

MARY ANN ATKINSON was born in Jun 1842 in Armagh, Northern Ireland. She died on 28 Apr 1905 in Baker, Oregon, USA (Pochahontas). She married Daniel Boone KRETZER, son of John KRETZER and Susanna Mae GALLENTINE on 11 Feb 1872 in Andrew, Missouri, USA. He was born on 31 Jan 1849 in Ohio, USA. He died on 26 Mar 1909 in Colfax, Whitman, Washington, USA. 

JANE ATKINSON was born in May 1844 in Armagh, Northern Ireland. She died on 11 Mar 1904 in St Joseph, Buchanan, Missouri, USA. She married David ATKINSON, son of Henry ATKINSON and Anne WILEY on 13 Aug 1871 in Andrew, Missouri, USA. He was born on 03 Mar 1854 in Armagh, Northern Ireland. He died on 17 Mar 1918 in St Joseph, Buchanan, Missouri, USA (Ensworth Hospital). NOTE: Jane may have been born in Missouri, USA?