Hi
I believe Etta's maiden name is Benett. When she first married Matthew they lived with Etta's parents. It states that Matthew was the son-in-law. Joseph and Jennie Benett.
They list Etta as Ella, probably typo. 1880 they say Etta M, then again 1900 when Etta M is listed with her mother living with her , its says Jennie Benett.

JUST A LONG SHOT, I did a search for Olive born about 1851 in Hamilton county in 1860 census, only one I came up with was a Olive Paige. She had a brother Charles.Its worth checking into.