Mandy,
I am convinced that the Elizabeth Stout shown with Isaac in the 1850 census is indeed Elizabeth Stout Thompson. Her husband, Archibald Thompson, died in 1834. She apparently moved in with Isaac, taking with her their youngest daughter, Elizabeth A. Thompson.
I next found Elizabeth Stout in the 1870 Shelby County census next to her daughter, Elizabeth Thompson Winget and her husband Wm. J. Winget and his mother Nancy Winget.
I find it very interesting that Elizabeth reverted to using her maiden name after the death of her husband. That seems to be most unusual in that era. Have you any clues as to why she might have done that?
My research is most concerned with Archibald Thompson and his siblings. If you have any information on him, I would really appreciate a copy.
Regards,
charlie