Swanton, ca 1840, could also be Fulton Co. OH or possibly Riga Twp., Lenawee Co. MI. The Lucas/Fulton County line runs through Swanton and parts north of Swanton were in Michigan.
I don't have the 1840 Lucas index but the 1870 index shows a Caroline A. and Walter C. STINSON in Richfield Twp., Lucas Co.
Also, a Walter C. STINSON filed for a military pension as an invalid on 8 Dec 1890 and his wife, Caroline A. filed as a widow on 26 Apr? (month and year illegible). Both requests were filed in Michigan. Walter served with the 128th Ohio Infantry Regiment.