Regarding families relocating en masse: On 1850 MO-Cass-District 16-Images 118 & 119 find Abigail Todd age 28 of Kentucky. She was your ancestor's sister and wed Matthew Todd, 1 Nov 1849 in Cass, MO. Note the blending of Todd and Owens children. For me, that's reason to suspect husband/wife were previously wed? Lastly, find Greenberry Owens with wife Susannah (nee: Clark) in 1850/1860 Cass, MO. They wed 8 Dec 1839 in Floyd, KY and he was another of your ancestor's brothers. Before I forget, I'm not related or acquainted!