States: Iowa: Fremont
My Thomas McKee did not have a daughter Jennie, to the best of my knowledge. I have a John David McKee (1821-1900) said to be buried in Monroe Cemetery, Imogene, Fremont County, Iowa. He had a daughter Ella Jane (or June), four years old at the 1860 census in Marion Twp, Linn County, Iowa, who married a Sylvester Manning. She died in 1892 according to my information but I don't know where. Maybe this is your Jennie. I need to verify this information, at any rate.