Hello. Thank you for the replies.
The Dallas Co Gen. Society found very little information. The Thos E. Fletcher buried at Storm Lake Cemetery is someone else, who amazingly has the exact same name and birthdate, but is from Ohio. Besides, my Thos Fletcher is alive in 1885, living with his wife in Perry.

I've checked the Perry papers online, too, with minimal success. The 1861 move date comes from a county biography of Ansel Fletcher (History of Guthrie and Adair Counties, Iowa. Springfield, IL, USA: Continental Historical, 1884) which also mentions his sister, Sarah.

Information about the William & Mahala Fletcher Holmes family comes from a county bio, too: Past and Present of Buena Vista County, Iowa, 1909, http://www.rootsweb.com/~iabuenav/past_present_1909_bios/

Last, some family members moved to Polk County Iowa, where relatives lived. Lewis & Kneeland buried in Mitchellville Cemetery.

Mahala is buried at Storm Lake Cemetery.
Ansel was living in Cerro Gordo County. After his death, his family moved to California.

Hope this is helpful,

Debian