I have a DeMars that moved to Minn. The father was Thomas DeMars. Do not know the mother. The family was moving to Minn. and the parents died of dysentary on the way. The children went on to Stillwater and were raised by an aunt. My greatgrandmother was Mary Jane DeMars born in Fostoria,Ohio. Both her parents were born in Ohio(According to 1880 Census). I found a Margaret DeMars Jourdain and a Monica DeMars that could be Aunts or Sisters to Mary Jane. I think they may be Aunts as I was told by an aunt that the family that raised the children were named Jourdain. Let me know if any of this story sounds familiar to you.