I didn't find Jonas in the 1860 census in Indiana. I did find a Jonas Fauss 22 living in Westmoreland County, PA. I also found a Jonas Fause 13 in the 1850 again in Westmoreland County. Unfortunately neither were with his parents although they may have been related somehow.
Oddly I could not find where he received a Civil War pension.
His obituary might list siblings although I suspect he may have been a lone orphan, but you never know.