Subsequent to the original posting, I located a Frederick Sefferman (aka, Siefferman) on the Florida Militia Muster Rolls, Seminole Indian Wars, Published at St. Augustine, FL, by Florida Dept. of Military Affairs. He was a Sgt. in the U.S. Army ref: Vol. 02, Pg. Nos. 094-95.He was the brother of my gg-grandmother Johannah Riebecca Siefferman (Geibel) Specht. They had a sister named Carolina who his letter appeared to have been written to. This appears to be the family connection and dates narrowed down to Jan - July 1838, Second Seminole Indian War, FL.