I saw your posting on Genealogy.com.I have the same Mary in my information.
Mary E. Ables 1850 Census, IA, Henry Co., New London Twp., pg. 184 Mary E. Ables, 2, b. IA.Listed with parents Alexander & Lucy Ables and 4 siblings
1860 Census, IA, Lucas Co., English Twp., pg. 557 Mary E. Ables, 12 F, b. IA, in school past year.Listed with parents Alexander & Lucy and 7 siblings.
1870 Census, IA, Henry Co., Salem Twp., pg. 312 Mary E. Pigeon, 22, b. IA, keeps house.Listed with husband, Isaac M., 33 b. IA, two children,Walter 2, & Harry 1.Also listed were in-laws, Isaac Pigeon, 77 b. NC, and Phoebe Pigeon, 76 b. NC
I have Mary's parents as: Alexander Ables (b. 1815, Guernsey Co., OH, d. 1898 Labette Co., KS)and Lucy Parks Underwood (b. 1818, OH, d. 1888 Labette Co., KS)